Changed ParseDataText function return values

CHANGELOG.md

@@ -1,3 +1,9 @@
+# v0.20.0
+
+* Added support of binding
+* Added "binding" argument to CreateViewFromResources, CreateViewFromText, and CreateViewFromObject functions
+* Changed ParseDataText function return values
+
 # v0.19.0
 
 * Added support of drag-and-drop
@@ -5,7 +11,7 @@
 
 # v0.18.2
 
-* fixed typo: GetShadowPropertys -> GetShadowProperty
+* fixed typo: GetShadowProperties -> GetShadowProperty
 
 # v0.18.0
 

README-ru.md

@@ -161,8 +161,8 @@ SizeUnit объявлена как
 | "sub(<arg1>, <arg2>)"        | SubSize(arg0, arg1 any)              | находит разность значений аргументов            |
 | "mul(<arg1>, <arg2>)"        | MulSize(arg0, arg1 any)              | находит результат умножения значений аргументов |
 | "div(<arg1>, <arg2>)"        | DivSize(arg0, arg1 any)              | находит результат деления значений аргументов   |
-| "rem(<arg1>, <arg2>)"        | ModSize(arg0, arg1 any)              | находит остаток деления значений аргументов, результат имеет тотже знак что и делимое   |
-| "mod(<arg1>, <arg2>)"        | ModSize(arg0, arg1 any)              | находит остаток деления значений аргументов, результат имеет тотже знак что и делитель   |
+| "rem(<arg1>, <arg2>)"        | ModSize(arg0, arg1 any)              | находит остаток деления значений аргументов, результат имеет тот же знак что и делимое   |
+| "mod(<arg1>, <arg2>)"        | ModSize(arg0, arg1 any)              | находит остаток деления значений аргументов, результат имеет тот же знак что и делитель   |
 | "round(<arg1>, <arg2>)"      | RoundSize(arg0, arg1 any)            | округляет первый аргумент до ближайшего целого числа кратного второму аргументу   |
 | "round-up(<arg1>, <arg2>)"   | RoundUpSize(arg0, arg1 any)          | округляет первый аргумент до ближайшего большего целого числа, кратного второму аргументу   |
 | "round-down(<arg1>, <arg2>)" | RoundDownSize(arg0, arg1 any)        | округляет первый аргумент до ближайшего меньшего целого числа кратного второму аргументу   |
@@ -1086,7 +1086,7 @@ RadiusProperty, а не структура BoxRadius. Получить стру
 
 Получить значение данного свойства можно с помощью функции
 
-	func GetShadowPropertys(view View, subviewID ...string) []ShadowProperty
+	func GetShadowProperties(view View, subviewID ...string) []ShadowProperty
 
 Если тень не задана, то данная функция вернет пустой массив
 
@@ -2291,14 +2291,14 @@ radius необходимо передать nil
 
 #### Свойство "drag-data"
 
-Для того чтобы сделать View перетаскиваемым ему неоходимо задать свойство "drag-data" (константа DragData).
+Для того чтобы сделать View перетаскиваемым ему необходимо задать свойство "drag-data" (константа DragData).
 Данное свойство задает множество перетаскиваемых данных в виде ключ:значение и имеет тип:
 
 	map[string]string
 
 В качестве ключей рекомендуется использовать mime-тип значения. 
-Например, если в перетаскиваемыми данными асляется текст, то ключем должен быть "text/plain", если jpeg-изображение, то "image/jpg" и т.п. 
-Но это только рекомендация, ключем может быть любой текст. 
+Например, если в перетаскиваемыми данными является текст, то ключом должен быть "text/plain", если jpeg-изображение, то "image/jpg" и т.п. 
+Но это только рекомендация, ключом может быть любой текст. 
 
 Пример
 
@@ -2318,7 +2318,7 @@ radius необходимо передать nil
 По умолчанию при перетаскивании перемещается весь View. Часто это бывает не удобно, например если View очень большой.
 
 Свойство "drag-image" (константа DragImage) типа string позволяет задать картинку, которая будет отображаться вместо View при перетаскивании.
-В качестве значения "drag-image" задаеться:
+В качестве значения "drag-image" задается:
 * Имя изображения в ресурсах приложения
 * Константа изображения
 * URL изображения
@@ -2442,15 +2442,15 @@ radius необходимо передать nil
 
 #### События "drag-enter-event", "drag-leave-event" и "drag-over-event"
 
-События "drag-enter-event", "drag-leave-event" и "drag-over-event" генерируются только для View приемника перетескиваемого объекта.
+События "drag-enter-event", "drag-leave-event" и "drag-over-event" генерируются только для View приемника перетаскиваемого объекта.
 
-Событие "drag-enter-event" генерируется когда перетаскиваемый оъект входит в область View приемника.
+Событие "drag-enter-event" генерируется когда перетаскиваемый объект входит в область View приемника.
 
-Событие "drag-leave-event" генерируется когда перетаскиваемый оъект покидает область View приемника.
+Событие "drag-leave-event" генерируется когда перетаскиваемый объект покидает область View приемника.
 
-Событие "drag-over-event" генерируется c определенным интервалом (несколько раз в секунду) пока перетаскиваемый оъект находится область View приемника.
+Событие "drag-over-event" генерируется c определенным интервалом (несколько раз в секунду) пока перетаскиваемый объект находится область View приемника.
 
-Пример, меняем цвет рамки с серой на красную когда перетаскиваемый оъект находится над областью приемника
+Пример, меняем цвет рамки с серой на красную когда перетаскиваемый объект находится над областью приемника
 
 	view.SetParams(rui.Params{
 		rui.DragEnterEvent: func(view rui.View, event rui.DragAndDropEvent)) {
@@ -3834,7 +3834,7 @@ float32, float64, int, int8…int64, uint, uint8…uint64.
 
 Между пунктами списка можно добавлять разделителями. Для этого используется свойство "item-separators" (константа ItemSeparators).
 Данному свойству присваивается массив индексов пунктов после которых необходимо добавить разделители. 
-Свойству "item-separators" могут присваиваться теже типы данных что и свойству "disabled-items".
+Свойству "item-separators" могут присваиваться те же типы данных что и свойству "disabled-items".
 Прочитать значение свойства "item-separators" можно с помощью функции
 
 	func GetDropDownItemSeparators(view View, subviewID ...string) []int
@@ -4085,7 +4085,7 @@ int свойство "current" (константа Current). Значение "c
 с помощью int свойств "checkbox-horizontal-align" и "checkbox-vertical-align" (константы
 CheckboxHorizontalAlign и CheckboxVerticalAlign)
 
-Свойство "checkbox-horizontal-align" (константа СheckboxHorizontalAlign) может принимать следующие значения:
+Свойство "checkbox-horizontal-align" (константа CheckboxHorizontalAlign) может принимать следующие значения:
 
 | Значение | Константа    | Имя      | Расположение чекбокса                           |
 |:--------:|--------------|----------|-------------------------------------------------|
@@ -4647,7 +4647,7 @@ rotation - угол поворота эллипса относительно ц
 Метод NewPath() создает пустую фигуру. Далее вы должны описать фигуру используя методы интерфейса Path
 
 Метод NewPathFromSvg(data string) Path создает фигуру описанную в параметре data. 
-Параметр data является описанием фигуры в формате елемента <path> svg изображения. Например
+Параметр data является описанием фигуры в формате элемента <path> svg изображения. Например
 
 	path := canvas.NewPathFromSvg("M 30,0 C 30,0 27,8.6486 17,21.622 7,34.595 0,40 0,40 0,40 6,44.3243 17,58.378 28,72.432 30,80 30,80 30,80 37.8387,65.074 43,58.378 53,45.405 60,40 60,40 60,40 53,34.5946 43,21.622 33,8.649 30,0 30,0 Z")
 
@@ -4827,7 +4827,7 @@ AudioPlayer и VideoPlayer это элементы которые предназ
 
 ### Свойство "src"
 
-Свойство "src" (константа Source) задает один или несколько источников медиафайлов. Свойство "src" может принимать
+Свойство "src" (константа Source) задает один или несколько источников медиа файлов. Свойство "src" может принимать
 значение следующих типов:
 
 * string,
@@ -4872,7 +4872,7 @@ AudioPlayer и VideoPlayer это элементы которые предназ
 |:--------:|-----------------|------------|----------------------------------------------------------------------------------------|
 | 0	       | PreloadNone     | "none"     | Медиа файл не должен быть предварительно загружен                                      |
 | 1	       | PreloadMetadata | "metadata" | Предварительно загружаются только метаданные                                           |
-| 2	       | PreloadAuto     | "auto"     | Весь медиафайл может быть загружен, даже если пользователь не должен его использовать. |
+| 2	       | PreloadAuto     | "auto"     | Весь медиа файл может быть загружен, даже если пользователь не должен его использовать.|
 
 Значение по умолчанию PreloadAuto (2)
 
@@ -5704,6 +5704,79 @@ Safari и Firefox.
 Для получения объекта используется метод Object.
 Для получения элементов массива используются методы ArraySize, ArrayElement и ArrayElements
 
+## Связывание (binding)
+
+Механизм связывания предназначен для задания обработчиков событий и слушателей изменений в ресурсах приложений.
+
+Рассмотрим пример:
+
+Файл ресурсов описывающий кнопку button.rui
+
+	Button {
+		click-event = ButtonClick,
+	}
+
+Код для создания этой кнопки из ресурсов
+
+	type button struct {
+		view rui.View
+	}
+
+	func createButton(session rui.Session) rui.View {
+		return rui.CreateViewFromResources(session, "button.rui", new(button))
+	}
+
+	func (button *button) OnCreate(view rui.View) {
+		button.view = view
+	}
+
+	func (button *button) ButtonClick() {
+		rui.DebugLog("Button clicked")
+	}
+
+В данном примере в файле ресурсов указано, что в качестве обработчика клика надо использовать функцию с именем "ButtonClick".
+При создании View из ресурсов с помощью функции CreateViewFromResources в качестве третьего параметра задается объект связывания.
+При возникновении события "click-event" система будет искать в связанном объекте один из следующих методов
+
+	ButtonClick()
+	ButtonClick(rui.View)
+	ButtonClick(rui.MouseEvent)
+	ButtonClick(rui.View, rui.MouseEvent)
+
+Система найдет метод ButtonClick() и вызовет его.
+
+Также для связанного объекта может задаваться опциональный метод 
+
+	OnCreate(view rui.View)
+
+Данный метод вызывается функциями CreateViewFromText, CreateViewFromResources и CreateViewFromObject после создания View.
+В данном примере этот метод используется для сохранения указателя на созданный View.
+
+Теперь рассмотрим как добавить отслеживание изменения свойств. 
+Для этого добавим в пример слушателя изменения свойства "background-color" в свойство "change-listeners"
+
+	Button {
+		click-event = ButtonClick,
+		change-listeners = {
+			background-color = BackgroundColorChanged,
+		},
+	}
+
+И добавим соответствующий метод
+
+	func (button *button) BackgroundColorChanged() {
+		rui.DebugLog("Background color changed")
+	}
+
+Данный метод может иметь одно из следующих описаний
+
+	BackgroundColorChanged()
+	BackgroundColorChanged(rui.View)
+	BackgroundColorChanged(rui.PropertyName)
+	BackgroundColorChanged(rui.View, rui.PropertyName)
+
+Важное замечание: Все методы вызываемые через связывание должны быть публичными (начинаться с большой буквы)
+
 ## Ресурсы
 
 Ресурсы (картинки, темы, переводы и т.д.) с которыми работает приложение должны размещаться по

README.md

@@ -520,7 +520,7 @@ For the "edit-text-changed" event, this
 * func(newText string)
 * []func(editor EditView, newText string)
 * []func(newText string)
-* []any содержащий только func(editor EditView, newText string) и func(newText string)
+* []any containing only func(editor EditView, newText string) и func(newText string)
 
 And the "edit-text-changed" property always stores and returns []func(EditView, string).
 
@@ -1062,7 +1062,7 @@ The ShadowProperty text representation has the following format:
 
 You can get the value of "shadow" property using the function
 
-	func GetShadowPropertys(view View, subviewID ...string) []ShadowProperty
+	func GetShadowProperties(view View, subviewID ...string) []ShadowProperty
 
 If no shadow is specified, then this function will return an empty array
 
@@ -2135,7 +2135,7 @@ You can get lists of pointer event listeners using the functions:
 
 ### Touch events
 
-These events are used to track multipoint touches. Single touches emulate mouse events.
+These events are used to track multi point touches. Single touches emulate mouse events.
 If you do not need to track multi-point touches, then it is easier to use mouse events
 
 | Event          | Constant    | Description                          |
@@ -5720,6 +5720,80 @@ using the SetResourcePath function before creating the Application:
 		app.Start("localhost:8000")
 	}
 
+## Binding
+
+The binding mechanism is designed to set event handlers and listeners for changes in application resources.
+
+Let's look at an example:
+
+The resource file ("button.rui") describing the button: 
+
+	Button {
+		click-event = ButtonClick,
+	}
+
+The code to create this button from resources
+
+	type button struct {
+		view rui.View
+	}
+
+	func createButton(session rui.Session) rui.View {
+		return rui.CreateViewFromResources(session, "button.rui", new(button))
+	}
+
+	func (button *button) OnCreate(view rui.View) {
+		button.view = view
+	}
+
+	func (button *button) ButtonClick() {
+		rui.DebugLog("Button clicked")
+	}
+
+In this example, the resource file specifies that a function named "ButtonClick" should be used as the click handler.
+When creating a View from resources using the CreateViewFromResources function, the binding object is specified as the third parameter.
+When a "click-event" occurs, the system will look for one of the following methods in the binding object
+
+	ButtonClick()
+	ButtonClick(rui.View)
+	ButtonClick(rui.MouseEvent)
+	ButtonClick(rui.View, rui.MouseEvent)
+
+The system will find the ButtonClick() method and call it.
+
+The optional method OnCreate can also be specified for the associated object
+
+	OnCreate(view rui.View)
+
+This method is called by the CreateViewFromText, CreateViewFromResources, and CreateViewFromObject functions after the View has been created.
+In this example, this method is used to save a pointer to the created View.
+
+Now let's look at how to add property change tracking.
+
+To do this, let's add a property change listener "background-color" to the property "change-listeners" in the example.
+
+	Button {
+		click-event = ButtonClick,
+		change-listeners = {
+			background-color = BackgroundColorChanged,
+		},
+	}
+
+And we will add the corresponding method
+
+	func (button *button) BackgroundColorChanged() {
+		rui.DebugLog("Background color changed")
+	}
+
+This method can have one of the following descriptions
+
+	BackgroundColorChanged()
+	BackgroundColorChanged(rui.View)
+	BackgroundColorChanged(rui.PropertyName)
+	BackgroundColorChanged(rui.View, rui.PropertyName)
+
+Important note: All methods called via binding must be public (start with a capital letter)
+
 ## Images for screens with different pixel densities
 
 If you need to add separate images to the resources for screens with different pixel densities, 
@@ -5919,7 +5993,7 @@ The library defines a number of constants and styles. You can override them in y
 
 System styles that you can override:
 
-| Style name          | Описание                                                            |
+| Style name          | Description                                                         |
 |---------------------|---------------------------------------------------------------------|
 | ruiApp              | This style is used to set the default text style (font, size, etc.) |
 | ruiView             | Default View Style                                                  |
@@ -6011,7 +6085,7 @@ Translation files must have the "rui" extension and the following format
 			<text 2> = <translation 2>,
 			…
 		},
-		<язык 2> = _{
+		<language 2> = _{
 			<text 1> = <translation 1>,
 			<text 2> = <translation 2>,
 			…

animation.go

@@ -2,6 +2,7 @@ package rui
 
 import (
 	"fmt"
+	"maps"
 	"math"
 	"strconv"
 	"strings"
@@ -209,7 +210,7 @@ type animationData struct {
 	usageCounter  int
 	view          View
 	listener      func(view View, animation AnimationProperty, event PropertyName)
-	oldListeners  map[PropertyName][]func(View, PropertyName)
+	oldListeners  map[PropertyName][]oneArgListener[View, PropertyName]
 	oldAnimation  []AnimationProperty
 }
 
@@ -661,7 +662,7 @@ func (animation *animationData) animationCSS(session Session) string {
 	buffer.WriteString(animation.keyFramesName)
 
 	if duration, ok := floatProperty(animation, Duration, session, 1); ok && duration > 0 {
-		buffer.WriteString(fmt.Sprintf(" %gs ", duration))
+		fmt.Fprintf(buffer, " %gs ", duration)
 	} else {
 		buffer.WriteString(" 1s ")
 	}
@@ -669,7 +670,7 @@ func (animation *animationData) animationCSS(session Session) string {
 	buffer.WriteString(timingFunctionCSS(animation, TimingFunction, session))
 
 	if delay, ok := floatProperty(animation, Delay, session, 0); ok && delay > 0 {
-		buffer.WriteString(fmt.Sprintf(" %gs", delay))
+		fmt.Fprintf(buffer, " %gs", delay)
 	} else {
 		buffer.WriteString(" 0s")
 	}
@@ -678,7 +679,7 @@ func (animation *animationData) animationCSS(session Session) string {
 		if iterationCount == 0 {
 			iterationCount = 1
 		}
-		buffer.WriteString(fmt.Sprintf(" %d ", iterationCount))
+		fmt.Fprintf(buffer, " %d ", iterationCount)
 	} else {
 		buffer.WriteString(" infinite ")
 	}
@@ -699,7 +700,7 @@ func (animation *animationData) animationCSS(session Session) string {
 func (animation *animationData) transitionCSS(buffer *strings.Builder, session Session) {
 
 	if duration, ok := floatProperty(animation, Duration, session, 1); ok && duration > 0 {
-		buffer.WriteString(fmt.Sprintf(" %gs ", duration))
+		fmt.Fprintf(buffer, " %gs ", duration)
 	} else {
 		buffer.WriteString(" 1s ")
 	}
@@ -707,7 +708,7 @@ func (animation *animationData) transitionCSS(buffer *strings.Builder, session S
 	buffer.WriteString(timingFunctionCSS(animation, TimingFunction, session))
 
 	if delay, ok := floatProperty(animation, Delay, session, 0); ok && delay > 0 {
-		buffer.WriteString(fmt.Sprintf(" %gs", delay))
+		fmt.Fprintf(buffer, " %gs", delay)
 	}
 }
 
@@ -979,11 +980,10 @@ func (style *viewStyle) Transition(tag PropertyName) AnimationProperty {
 }
 
 func (style *viewStyle) Transitions() map[PropertyName]AnimationProperty {
-	result := map[PropertyName]AnimationProperty{}
-	for tag, animation := range getTransitionProperty(style) {
-		result[tag] = animation
+	if transitions := getTransitionProperty(style); transitions != nil {
+		return maps.Clone(transitions)
 	}
-	return result
+	return map[PropertyName]AnimationProperty{}
 }
 
 func (style *viewStyle) SetTransition(tag PropertyName, animation AnimationProperty) {
@@ -1083,7 +1083,9 @@ func SetAnimated(rootView View, viewID string, tag PropertyName, value any, anim
 }
 
 // IsAnimationPaused returns "true" if an animation of the subview is paused, "false" otherwise.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func IsAnimationPaused(view View, subviewID ...string) bool {
 	return boolStyledProperty(view, subviewID, AnimationPaused, false)
 }

animationEvents.go

@@ -156,45 +156,6 @@ const (
 	AnimationIterationEvent PropertyName = "animation-iteration-event"
 )
 
-/*
-func setTransitionListener(properties Properties, tag PropertyName, value any) bool {
-	if listeners, ok := valueToOneArgEventListeners[View, string](value); ok {
-		if len(listeners) == 0 {
-			properties.setRaw(tag, nil)
-		} else {
-			properties.setRaw(tag, listeners)
-		}
-		return true
-	}
-	notCompatibleType(tag, value)
-	return false
-}
-
-func (view *viewData) removeTransitionListener(tag PropertyName) {
-	delete(view.properties, tag)
-	if view.created {
-		if js, ok := eventJsFunc[tag]; ok {
-			view.session.removeProperty(view.htmlID(), js.jsEvent)
-		}
-	}
-}
-
-func transitionEventsHtml(view View, buffer *strings.Builder) {
-	for _, tag := range []PropertyName{TransitionRunEvent, TransitionStartEvent, TransitionEndEvent, TransitionCancelEvent} {
-		if value := view.getRaw(tag); value != nil {
-			if js, ok := eventJsFunc[tag]; ok {
-				if listeners, ok := value.([]func(View, string)); ok && len(listeners) > 0 {
-					buffer.WriteString(js.jsEvent)
-					buffer.WriteString(`="`)
-					buffer.WriteString(js.jsFunc)
-					buffer.WriteString(`(this, event)" `)
-				}
-			}
-		}
-	}
-}
-*/
-
 func (view *viewData) handleTransitionEvents(tag PropertyName, data DataObject) {
 	if propertyName, ok := data.PropertyValue("property"); ok {
 		property := PropertyName(propertyName)
@@ -208,50 +169,11 @@ func (view *viewData) handleTransitionEvents(tag PropertyName, data DataObject)
 		}
 
 		for _, listener := range getOneArgEventListeners[View, PropertyName](view, nil, tag) {
-			listener(view, property)
+			listener.Run(view, property)
 		}
 	}
 }
 
-/*
-	func setAnimationListener(properties Properties, tag PropertyName, value any) bool {
-		if listeners, ok := valueToOneArgEventListeners[View, string](value); ok {
-			if len(listeners) == 0 {
-				properties.setRaw(tag, nil)
-			} else {
-				properties.setRaw(tag, listeners)
-			}
-			return true
-		}
-		notCompatibleType(tag, value)
-		return false
-	}
-
-func (view *viewData) removeAnimationListener(tag PropertyName) {
-	delete(view.properties, tag)
-	if view.created {
-		if js, ok := eventJsFunc[tag]; ok {
-			view.session.removeProperty(view.htmlID(), js.jsEvent)
-		}
-	}
-}
-
-func animationEventsHtml(view View, buffer *strings.Builder) {
-	for _, tag := range []PropertyName{AnimationStartEvent, AnimationEndEvent, AnimationIterationEvent, AnimationCancelEvent} {
-		if value := view.getRaw(tag); value != nil {
-			if js, ok := eventJsFunc[tag]; ok {
-				if listeners, ok := value.([]func(View, string)); ok && len(listeners) > 0 {
-					buffer.WriteString(js.jsEvent)
-					buffer.WriteString(`="`)
-					buffer.WriteString(js.jsFunc)
-					buffer.WriteString(`(this, event)" `)
-				}
-			}
-		}
-	}
-}
-*/
-
 func (view *viewData) handleAnimationEvents(tag PropertyName, data DataObject) {
 	if listeners := getOneArgEventListeners[View, string](view, nil, tag); len(listeners) > 0 {
 		id := ""
@@ -263,63 +185,135 @@ func (view *viewData) handleAnimationEvents(tag PropertyName, data DataObject) {
 			}
 		}
 		for _, listener := range listeners {
-			listener(view, id)
+			listener.Run(view, id)
 		}
 	}
 }
 
 // GetTransitionRunListeners returns the "transition-run-event" listener list.
 // If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetTransitionRunListeners(view View, subviewID ...string) []func(View, string) {
-	return getOneArgEventListeners[View, string](view, subviewID, TransitionRunEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.View, string),
+//   - func(rui.View),
+//   - func(string),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetTransitionRunListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, string](view, subviewID, TransitionRunEvent)
 }
 
 // GetTransitionStartListeners returns the "transition-start-event" listener list.
 // If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetTransitionStartListeners(view View, subviewID ...string) []func(View, string) {
-	return getOneArgEventListeners[View, string](view, subviewID, TransitionStartEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.View, string),
+//   - func(rui.View),
+//   - func(string),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetTransitionStartListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, string](view, subviewID, TransitionStartEvent)
 }
 
 // GetTransitionEndListeners returns the "transition-end-event" listener list.
 // If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetTransitionEndListeners(view View, subviewID ...string) []func(View, string) {
-	return getOneArgEventListeners[View, string](view, subviewID, TransitionEndEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.View, string),
+//   - func(rui.View),
+//   - func(string),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetTransitionEndListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, string](view, subviewID, TransitionEndEvent)
 }
 
 // GetTransitionCancelListeners returns the "transition-cancel-event" listener list.
 // If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetTransitionCancelListeners(view View, subviewID ...string) []func(View, string) {
-	return getOneArgEventListeners[View, string](view, subviewID, TransitionCancelEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.View, string),
+//   - func(rui.View),
+//   - func(string),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetTransitionCancelListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, string](view, subviewID, TransitionCancelEvent)
 }
 
 // GetAnimationStartListeners returns the "animation-start-event" listener list.
 // If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetAnimationStartListeners(view View, subviewID ...string) []func(View, string) {
-	return getOneArgEventListeners[View, string](view, subviewID, AnimationStartEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.View, string),
+//   - func(rui.View),
+//   - func(string),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetAnimationStartListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, string](view, subviewID, AnimationStartEvent)
 }
 
 // GetAnimationEndListeners returns the "animation-end-event" listener list.
 // If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetAnimationEndListeners(view View, subviewID ...string) []func(View, string) {
-	return getOneArgEventListeners[View, string](view, subviewID, AnimationEndEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.View, string),
+//   - func(rui.View),
+//   - func(string),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetAnimationEndListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, string](view, subviewID, AnimationEndEvent)
 }
 
 // GetAnimationCancelListeners returns the "animation-cancel-event" listener list.
 // If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetAnimationCancelListeners(view View, subviewID ...string) []func(View, string) {
-	return getOneArgEventListeners[View, string](view, subviewID, AnimationCancelEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.View, string),
+//   - func(rui.View),
+//   - func(string),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetAnimationCancelListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, string](view, subviewID, AnimationCancelEvent)
 }
 
 // GetAnimationIterationListeners returns the "animation-iteration-event" listener list.
 // If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetAnimationIterationListeners(view View, subviewID ...string) []func(View, string) {
-	return getOneArgEventListeners[View, string](view, subviewID, AnimationIterationEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.View, string),
+//   - func(rui.View),
+//   - func(string),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetAnimationIterationListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, string](view, subviewID, AnimationIterationEvent)
 }

animationRun.go

@@ -1,5 +1,7 @@
 package rui
 
+import "slices"
+
 func (animation *animationData) Start(view View, listener func(view View, animation AnimationProperty, event PropertyName)) bool {
 	if view == nil {
 		ErrorLog("nil View in animation.Start() function")
@@ -13,28 +15,22 @@ func (animation *animationData) Start(view View, listener func(view View, animat
 	animation.listener = listener
 
 	animation.oldAnimation = nil
+
+	//if  getOneArgEventListeners[View, PropertyName](view, nil, Animation)
 	if value := view.Get(Animation); value != nil {
 		if oldAnimation, ok := value.([]AnimationProperty); ok && len(oldAnimation) > 0 {
 			animation.oldAnimation = oldAnimation
 		}
 	}
 
-	animation.oldListeners = map[PropertyName][]func(View, PropertyName){}
+	animation.oldListeners = map[PropertyName][]oneArgListener[View, PropertyName]{}
 
 	setListeners := func(event PropertyName, listener func(View, PropertyName)) {
-		var listeners []func(View, PropertyName) = nil
-		if value := view.Get(event); value != nil {
-			if oldListeners, ok := value.([]func(View, PropertyName)); ok && len(oldListeners) > 0 {
-				listeners = oldListeners
-			}
-		}
-
-		if listeners == nil {
-			view.Set(event, listener)
-		} else {
-			animation.oldListeners[event] = listeners
-			view.Set(event, append(listeners, listener))
+		listeners := getOneArgEventListeners[View, PropertyName](view, nil, event)
+		if len(listeners) > 0 {
+			animation.oldListeners[event] = slices.Clone(listeners)
 		}
+		view.Set(event, append(listeners, newOneArgListenerVE(listener)))
 	}
 
 	setListeners(AnimationStartEvent, animation.onAnimationStart)
@@ -49,7 +45,7 @@ func (animation *animationData) Start(view View, listener func(view View, animat
 func (animation *animationData) finish() {
 	if animation.view != nil {
 		for _, event := range []PropertyName{AnimationStartEvent, AnimationEndEvent, AnimationCancelEvent, AnimationIterationEvent} {
-			if listeners, ok := animation.oldListeners[event]; ok {
+			if listeners, ok := animation.oldListeners[event]; ok && len(listeners) > 0 {
 				animation.view.Set(event, listeners)
 			} else {
 				animation.view.Remove(event)
@@ -63,7 +59,7 @@ func (animation *animationData) finish() {
 			animation.view.Set(Animation, "")
 		}
 
-		animation.oldListeners = map[PropertyName][]func(View, PropertyName){}
+		animation.oldListeners = map[PropertyName][]oneArgListener[View, PropertyName]{}
 
 		animation.view = nil
 		animation.listener = nil

appServer.go

@@ -164,64 +164,68 @@ func (app *application) postHandler(w http.ResponseWriter, req *http.Request) {
 			DebugLog(message)
 		}
 
-		if obj := ParseDataText(message); obj != nil {
-			var session Session = nil
-			var response chan string = nil
+		obj, err := ParseDataText(message)
+		if err != nil {
+			ErrorLog(err.Error())
+			return
+		}
 
-			if cookie, err := req.Cookie("session"); err == nil {
-				sessionID, err := strconv.Atoi(cookie.Value)
-				if err != nil {
-					ErrorLog(err.Error())
-				} else if info, ok := app.sessions[sessionID]; ok && info.response != nil {
-					response = info.response
-					session = info.session
-				}
-			}
-
-			command := obj.Tag()
-			startSession := false
-
-			if session == nil || command == "startSession" {
-				events := make(chan DataObject, 1024)
-				bridge := createHttpBridge(req)
-				response = bridge.response
-				answer := ""
-				session, answer = app.startSession(obj, events, bridge, response)
-
-				bridge.writeMessage(answer)
-				session.onStart()
-				if command == "session-resume" {
-					session.onResume()
-				}
-				bridge.sendResponse()
-
-				setSessionIDCookie(w, session.ID())
-				startSession = true
-
-				go sessionEventHandler(session, events, bridge)
-			}
-
-			if !startSession {
-				switch command {
-				case "nop":
-					session.sendResponse()
-
-				case "session-close":
-					session.onFinish()
-					session.App().removeSession(session.ID())
-					return
-
-				default:
-					if !session.handleAnswer(command, obj) {
-						session.addToEventsQueue(obj)
-					}
+		var session Session = nil
+		var response chan string = nil
+
+		if cookie, err := req.Cookie("session"); err == nil {
+			sessionID, err := strconv.Atoi(cookie.Value)
+			if err != nil {
+				ErrorLog(err.Error())
+			} else if info, ok := app.sessions[sessionID]; ok && info.response != nil {
+				response = info.response
+				session = info.session
+			}
+		}
+
+		command := obj.Tag()
+		startSession := false
+
+		if session == nil || command == "startSession" {
+			events := make(chan DataObject, 1024)
+			bridge := createHttpBridge(req)
+			response = bridge.response
+			answer := ""
+			session, answer = app.startSession(obj, events, bridge, response)
+
+			bridge.writeMessage(answer)
+			session.onStart()
+			if command == "session-resume" {
+				session.onResume()
+			}
+			bridge.sendResponse()
+
+			setSessionIDCookie(w, session.ID())
+			startSession = true
+
+			go sessionEventHandler(session, events, bridge)
+		}
+
+		if !startSession {
+			switch command {
+			case "nop":
+				session.sendResponse()
+
+			case "session-close":
+				session.onFinish()
+				session.App().removeSession(session.ID())
+				return
+
+			default:
+				if !session.handleAnswer(command, obj) {
+					session.addToEventsQueue(obj)
 				}
 			}
+		}
 
+		io.WriteString(w, <-response)
+		for len(response) > 0 {
 			io.WriteString(w, <-response)
-			for len(response) > 0 {
-				io.WriteString(w, <-response)
-			}
 		}
 	}
 }
@@ -241,58 +245,61 @@ func (app *application) socketReader(bridge *wsBridge) {
 			DebugLog("🖥️ -> " + message)
 		}
 
-		if obj := ParseDataText(message); obj != nil {
-			command := obj.Tag()
-			switch command {
-			case "startSession":
-				answer := ""
+		obj, err := ParseDataText(message)
+		if err != nil {
+			ErrorLog(err.Error())
+			return
+		}
+
+		switch command := obj.Tag(); command {
+		case "startSession":
+			answer := ""
+			if session, answer = app.startSession(obj, events, bridge, nil); session != nil {
+				if !bridge.writeMessage(answer) {
+					return
+				}
+				session.onStart()
+				go sessionEventHandler(session, events, bridge)
+			}
+
+		case "reconnect":
+			session = nil
+			if sessionText, ok := obj.PropertyValue("session"); ok {
+				if sessionID, err := strconv.Atoi(sessionText); err == nil {
+					if info, ok := app.sessions[sessionID]; ok {
+						session = info.session
+						session.setBridge(events, bridge)
+
+						go sessionEventHandler(session, events, bridge)
+						session.onReconnect()
+					} else {
+						DebugLogF("Session #%d not exists", sessionID)
+					}
+				} else {
+					ErrorLog(`strconv.Atoi(sessionText) error: ` + err.Error())
+				}
+			} else {
+				ErrorLog(`"session" key not found`)
+			}
+
+			if session == nil {
+				/* answer := ""
 				if session, answer = app.startSession(obj, events, bridge, nil); session != nil {
 					if !bridge.writeMessage(answer) {
 						return
 					}
 					session.onStart()
 					go sessionEventHandler(session, events, bridge)
+					bridge.writeMessage("restartSession();")
 				}
+				*/
+				bridge.writeMessage("reloadPage();")
+				return
+			}
 
-			case "reconnect":
-				session = nil
-				if sessionText, ok := obj.PropertyValue("session"); ok {
-					if sessionID, err := strconv.Atoi(sessionText); err == nil {
-						if info, ok := app.sessions[sessionID]; ok {
-							session = info.session
-							session.setBridge(events, bridge)
-
-							go sessionEventHandler(session, events, bridge)
-							session.onReconnect()
-						} else {
-							DebugLogF("Session #%d not exists", sessionID)
-						}
-					} else {
-						ErrorLog(`strconv.Atoi(sessionText) error: ` + err.Error())
-					}
-				} else {
-					ErrorLog(`"session" key not found`)
-				}
-
-				if session == nil {
-					/* answer := ""
-					if session, answer = app.startSession(obj, events, bridge, nil); session != nil {
-						if !bridge.writeMessage(answer) {
-							return
-						}
-						session.onStart()
-						go sessionEventHandler(session, events, bridge)
-						bridge.writeMessage("restartSession();")
-					}
-					*/
-					bridge.writeMessage("reloadPage();")
-					return
-				}
-
-			default:
-				if !session.handleAnswer(command, obj) {
-					events <- obj
-				}
+		default:
+			if !session.handleAnswer(command, obj) {
+				events <- obj
 			}
 		}
 	}

background.go

@@ -78,6 +78,16 @@ func createBackground(obj DataObject) BackgroundElement {
 	return result
 }
 
+func parseBackgroundText(text string) BackgroundElement {
+	obj, err := ParseDataText(text)
+	if err != nil {
+		ErrorLog(err.Error())
+		return nil
+	}
+
+	return createBackground(obj)
+}
+
 func parseBackgroundValue(value any) []BackgroundElement {
 
 	switch value := value.(type) {
@@ -96,12 +106,8 @@ func parseBackgroundValue(value any) []BackgroundElement {
 				} else {
 					return nil
 				}
-			} else if obj := ParseDataText(el.Value()); obj != nil {
-				if element := createBackground(obj); element != nil {
-					background = append(background, element)
-				} else {
-					return nil
-				}
+			} else if element := parseBackgroundText(el.Value()); element != nil {
+				background = append(background, element)
 			} else {
 				return nil
 			}
@@ -125,21 +131,15 @@ func parseBackgroundValue(value any) []BackgroundElement {
 		return background
 
 	case string:
-		if obj := ParseDataText(value); obj != nil {
-			if element := createBackground(obj); element != nil {
-				return []BackgroundElement{element}
-			}
+		if element := parseBackgroundText(value); element != nil {
+			return []BackgroundElement{element}
 		}
 
 	case []string:
 		elements := make([]BackgroundElement, 0, len(value))
-		for _, element := range value {
-			if obj := ParseDataText(element); obj != nil {
-				if element := createBackground(obj); element != nil {
-					elements = append(elements, element)
-				} else {
-					return nil
-				}
+		for _, text := range value {
+			if element := parseBackgroundText(text); element != nil {
+				elements = append(elements, element)
 			} else {
 				return nil
 			}
@@ -148,18 +148,14 @@ func parseBackgroundValue(value any) []BackgroundElement {
 
 	case []any:
 		elements := make([]BackgroundElement, 0, len(value))
-		for _, element := range value {
-			switch element := element.(type) {
+		for _, val := range value {
+			switch val := val.(type) {
 			case BackgroundElement:
-				elements = append(elements, element)
+				elements = append(elements, val)
 
 			case string:
-				if obj := ParseDataText(element); obj != nil {
-					if element := createBackground(obj); element != nil {
-						elements = append(elements, element)
-					} else {
-						return nil
-					}
+				if element := parseBackgroundText(val); element != nil {
+					elements = append(elements, element)
 				} else {
 					return nil
 				}
@@ -268,14 +264,16 @@ func backgroundStyledPropery(view View, subviewID []string, tag PropertyName) []
 
 // GetBackground returns the view background.
 //
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetBackground(view View, subviewID ...string) []BackgroundElement {
 	return backgroundStyledPropery(view, subviewID, Background)
 }
 
 // GetMask returns the view mask.
 //
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetMask(view View, subviewID ...string) []BackgroundElement {
 	return backgroundStyledPropery(view, subviewID, Mask)
 }
@@ -284,7 +282,8 @@ func GetMask(view View, subviewID ...string) []BackgroundElement {
 //
 //	BorderBox (0), PaddingBox (1), ContentBox (2)
 //
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetBackgroundClip(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, BackgroundClip, 0, false)
 }
@@ -293,7 +292,8 @@ func GetBackgroundClip(view View, subviewID ...string) int {
 //
 //	BorderBox (0), PaddingBox (1), ContentBox (2)
 //
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetBackgroundOrigin(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, BackgroundOrigin, 0, false)
 }
@@ -302,7 +302,8 @@ func GetBackgroundOrigin(view View, subviewID ...string) int {
 //
 //	BorderBox (0), PaddingBox (1), ContentBox (2)
 //
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetMaskClip(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, MaskClip, 0, false)
 }
@@ -311,7 +312,8 @@ func GetMaskClip(view View, subviewID ...string) int {
 //
 //	BorderBox (0), PaddingBox (1), ContentBox (2)
 //
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetMaskOrigin(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, MaskOrigin, 0, false)
 }

backgroundRadialGradient.go

@@ -43,7 +43,7 @@ type backgroundRadialGradient struct {
 //
 // The following properties can be used:
 //   - "gradient" (Gradient) - Describes gradient stop points. This is a mandatory property while describing background gradients.
-//   - "center-x" (CenterX), "center-y" (CenterY) - Defines the gradient center point cooordinates.
+//   - "center-x" (CenterX), "center-y" (CenterY) - Defines the gradient center point coordinates.
 //   - "radial-gradient-radius" (RadialGradientRadius) - Defines radius of the radial gradient.
 //   - "radial-gradient-shape" (RadialGradientShape) - Defines shape of the radial gradient.
 //   - "repeating" (Repeating) - Defines whether stop points needs to be repeated after the last one.

border.go

@@ -610,7 +610,10 @@ func borderSet(properties Properties, tag PropertyName, value any) []PropertyNam
 	case Left, Right, Top, Bottom:
 		switch value := value.(type) {
 		case string:
-			if obj := ParseDataText(value); obj != nil {
+			obj, err := ParseDataText(value)
+			if err != nil {
+				ErrorLog(err.Error())
+			} else {
 				return setSingleBorderObject(tag, obj)
 			}
 

canvas.go

@@ -201,7 +201,7 @@ type Canvas interface {
 
 	// SetConicGradientFillStyle sets a conic gradient around a point
 	// to use inside shapes
-	//   * x, y - coordinates of the center of the conic gradient in pilels;
+	//   * x, y - coordinates of the center of the conic gradient in piles;
 	//   * startAngle - the angle at which to begin the gradient, in radians. The angle starts from a line going horizontally right from the center, and proceeds clockwise.
 	//   * startColor - the start color;
 	//   * endColor - the end color;
@@ -210,7 +210,7 @@ type Canvas interface {
 
 	// SetConicGradientFillStyle sets a conic gradient around a point
 	// to use inside shapes
-	//   * x, y - coordinates of the center of the conic gradient in pilels;
+	//   * x, y - coordinates of the center of the conic gradient in piles;
 	//   * startAngle - the angle at which to begin the gradient, in radians. The angle starts from a line going horizontally right from the center, and proceeds clockwise.
 	//   * startColor - the start color;
 	//   * endColor - the end color;
@@ -575,7 +575,7 @@ func (canvas *canvasData) SetLineDash(dash []float64, offset float64) {
 	for _, val := range dash {
 		buffer.WriteRune(lead)
 		lead = ','
-		buffer.WriteString(fmt.Sprintf("%g", val))
+		fmt.Fprintf(buffer, "%g", val))
 	}
 	buffer.WriteRune(']')
 

canvasView.go

@@ -1,5 +1,7 @@
 package rui
 
+import "reflect"
+
 // DrawFunction is the constant for "draw-function" property tag.
 //
 // Used by `CanvasView`.
@@ -55,7 +57,7 @@ func (canvasView *canvasViewData) removeFunc(tag PropertyName) []PropertyName {
 	if tag == DrawFunction {
 		if canvasView.getRaw(DrawFunction) != nil {
 			canvasView.setRaw(DrawFunction, nil)
-			canvasView.Redraw()
+			//canvasView.Redraw()
 			return []PropertyName{DrawFunction}
 		}
 		return []PropertyName{}
@@ -66,9 +68,14 @@ func (canvasView *canvasViewData) removeFunc(tag PropertyName) []PropertyName {
 
 func (canvasView *canvasViewData) setFunc(tag PropertyName, value any) []PropertyName {
 	if tag == DrawFunction {
-		if fn, ok := value.(func(Canvas)); ok {
-			canvasView.setRaw(DrawFunction, fn)
-		} else {
+		switch value := value.(type) {
+		case func(Canvas):
+			canvasView.setRaw(DrawFunction, value)
+
+		case string:
+			canvasView.setRaw(DrawFunction, value)
+
+		default:
 			notCompatibleType(tag, value)
 			return nil
 		}
@@ -94,8 +101,30 @@ func (canvasView *canvasViewData) Redraw() {
 	canvas := newCanvas(canvasView)
 	canvas.ClearRect(0, 0, canvasView.frame.Width, canvasView.frame.Height)
 	if value := canvasView.getRaw(DrawFunction); value != nil {
-		if drawer, ok := value.(func(Canvas)); ok {
+		switch drawer := value.(type) {
+		case func(Canvas):
 			drawer(canvas)
+
+		case string:
+			bind := canvasView.binding()
+			if bind == nil {
+				ErrorLogF(`There is no a binding object for call "%s"`, drawer)
+				break
+			}
+
+			val := reflect.ValueOf(bind)
+			method := val.MethodByName(drawer)
+			if !method.IsValid() {
+				ErrorLogF(`The "%s" method is not valid`, drawer)
+				break
+			}
+
+			methodType := method.Type()
+			if methodType.NumIn() == 1 && equalType(methodType.In(0), reflect.TypeOf(canvas)) {
+				method.Call([]reflect.Value{reflect.ValueOf(canvas)})
+			} else {
+				ErrorLogF(`Unsupported prototype of "%s" method`, drawer)
+			}
 		}
 	}
 	canvas.finishDraw()

checkbox.go

@@ -53,8 +53,8 @@ func (button *checkboxData) init(session Session) {
 	button.remove = button.removeFunc
 	button.changed = button.propertyChanged
 
-	button.setRaw(ClickEvent, []func(View, MouseEvent){checkboxClickListener})
-	button.setRaw(KeyDownEvent, []func(View, KeyEvent){checkboxKeyListener})
+	button.setRaw(ClickEvent, []oneArgListener[View, MouseEvent]{newOneArgListenerVE(checkboxClickListener)})
+	button.setRaw(KeyDownEvent, []oneArgListener[View, KeyEvent]{newOneArgListenerVE(checkboxKeyListener)})
 }
 
 func (button *checkboxData) Focusable() bool {
@@ -67,9 +67,9 @@ func (button *checkboxData) propertyChanged(tag PropertyName) {
 	case Checked:
 		session := button.Session()
 		checked := IsCheckboxChecked(button)
-		if listeners := GetCheckboxChangedListeners(button); len(listeners) > 0 {
+		if listeners := getOneArgEventListeners[Checkbox, bool](button, nil, CheckboxChangedEvent); len(listeners) > 0 {
 			for _, listener := range listeners {
-				listener(button, checked)
+				listener.Run(button, checked)
 			}
 		}
 
@@ -103,7 +103,7 @@ func (button *checkboxData) setFunc(tag PropertyName, value any) []PropertyName
 	switch tag {
 	case ClickEvent:
 		if listeners, ok := valueToOneArgEventListeners[View, MouseEvent](value); ok && listeners != nil {
-			listeners = append(listeners, checkboxClickListener)
+			listeners = append(listeners, newOneArgListenerVE(checkboxClickListener))
 			button.setRaw(tag, listeners)
 			return []PropertyName{tag}
 		}
@@ -111,7 +111,7 @@ func (button *checkboxData) setFunc(tag PropertyName, value any) []PropertyName
 
 	case KeyDownEvent:
 		if listeners, ok := valueToOneArgEventListeners[View, KeyEvent](value); ok && listeners != nil {
-			listeners = append(listeners, checkboxKeyListener)
+			listeners = append(listeners, newOneArgListenerVE(checkboxKeyListener))
 			button.setRaw(tag, listeners)
 			return []PropertyName{tag}
 		}
@@ -134,31 +134,17 @@ func (button *checkboxData) setFunc(tag PropertyName, value any) []PropertyName
 func (button *checkboxData) removeFunc(tag PropertyName) []PropertyName {
 	switch tag {
 	case ClickEvent:
-		button.setRaw(ClickEvent, []func(View, MouseEvent){checkboxClickListener})
+		button.setRaw(ClickEvent, []oneArgListener[View, MouseEvent]{newOneArgListenerVE(checkboxClickListener)})
 		return []PropertyName{ClickEvent}
 
 	case KeyDownEvent:
-		button.setRaw(KeyDownEvent, []func(View, KeyEvent){checkboxKeyListener})
+		button.setRaw(KeyDownEvent, []oneArgListener[View, KeyEvent]{newOneArgListenerVE(checkboxKeyListener)})
 		return []PropertyName{ClickEvent}
 	}
 
 	return button.viewsContainerData.removeFunc(tag)
 }
 
-/*
-func (button *checkboxData) changedCheckboxState(state bool) {
-	for _, listener := range GetCheckboxChangedListeners(button) {
-		listener(button, state)
-	}
-
-	buffer := allocStringBuilder()
-	defer freeStringBuilder(buffer)
-
-	button.htmlCheckbox(buffer, state)
-	button.Session().updateInnerHTML(button.htmlID()+"checkbox", buffer.String())
-}
-*/
-
 func checkboxClickListener(view View, _ MouseEvent) {
 	view.Set(Checked, !IsCheckboxChecked(view))
 	BlurView(view)
@@ -302,26 +288,41 @@ func checkboxVerticalAlignCSS(view View) string {
 }
 
 // IsCheckboxChecked returns true if the Checkbox is checked, false otherwise.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func IsCheckboxChecked(view View, subviewID ...string) bool {
 	return boolStyledProperty(view, subviewID, Checked, false)
 }
 
 // GetCheckboxVerticalAlign return the vertical align of a Checkbox subview: TopAlign (0), BottomAlign (1), CenterAlign (2)
-// If the second argument (subviewID) is not specified or it is "" then a left position of the first argument (view) is returned
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetCheckboxVerticalAlign(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, CheckboxVerticalAlign, LeftAlign, false)
 }
 
 // GetCheckboxHorizontalAlign return the vertical align of a Checkbox subview: LeftAlign (0), RightAlign (1), CenterAlign (2)
-// If the second argument (subviewID) is not specified or it is "" then a left position of the first argument (view) is returned
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetCheckboxHorizontalAlign(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, CheckboxHorizontalAlign, TopAlign, false)
 }
 
 // GetCheckboxChangedListeners returns the CheckboxChangedListener list of an Checkbox subview.
-// If there are no listeners then the empty list is returned
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetCheckboxChangedListeners(view View, subviewID ...string) []func(Checkbox, bool) {
-	return getOneArgEventListeners[Checkbox, bool](view, subviewID, CheckboxChangedEvent)
+// If there are no listeners then the empty list is returned.
+//
+// Result elements can be of the following types:
+//   - func(Checkbox, bool),
+//   - func(Checkbox),
+//   - func(bool),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetCheckboxChangedListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[Checkbox, bool](view, subviewID, CheckboxChangedEvent)
 }

colorPicker.go

@@ -106,13 +106,13 @@ func (picker *colorPickerData) propertyChanged(tag PropertyName) {
 		color := GetColorPickerValue(picker)
 		picker.Session().callFunc("setInputValue", picker.htmlID(), color.rgbString())
 
-		if listeners := GetColorChangedListeners(picker); len(listeners) > 0 {
+		if listeners := getTwoArgEventListeners[ColorPicker, Color](picker, nil, ColorChangedEvent); len(listeners) > 0 {
 			oldColor := Color(0)
 			if value := picker.getRaw("old-color"); value != nil {
 				oldColor = value.(Color)
 			}
 			for _, listener := range listeners {
-				listener(picker, color, oldColor)
+				listener.Run(picker, color, oldColor)
 			}
 		}
 
@@ -156,11 +156,11 @@ func (picker *colorPickerData) handleCommand(self View, command PropertyName, da
 				oldColor := GetColorPickerValue(picker)
 				picker.properties[ColorPickerValue] = color
 				if color != oldColor {
-					for _, listener := range GetColorChangedListeners(picker) {
-						listener(picker, color, oldColor)
+					for _, listener := range getTwoArgEventListeners[ColorPicker, Color](picker, nil, ColorChangedEvent) {
+						listener.Run(picker, color, oldColor)
 					}
 					if listener, ok := picker.changeListener[ColorPickerValue]; ok {
-						listener(picker, ColorPickerValue)
+						listener.Run(picker, ColorPickerValue)
 					}
 				}
 			}
@@ -172,7 +172,9 @@ func (picker *colorPickerData) handleCommand(self View, command PropertyName, da
 }
 
 // GetColorPickerValue returns the value of ColorPicker subview.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetColorPickerValue(view View, subviewID ...string) Color {
 	if view = getSubview(view, subviewID); view != nil {
 		if value, ok := colorProperty(view, ColorPickerValue, view.Session()); ok {
@@ -191,7 +193,18 @@ func GetColorPickerValue(view View, subviewID ...string) Color {
 
 // GetColorChangedListeners returns the ColorChangedListener list of an ColorPicker subview.
 // If there are no listeners then the empty list is returned
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetColorChangedListeners(view View, subviewID ...string) []func(ColorPicker, Color, Color) {
-	return getTwoArgEventListeners[ColorPicker, Color](view, subviewID, ColorChangedEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.ColorPicker, rui.Color, rui.Color),
+//   - func(rui.ColorPicker, rui.Color),
+//   - func(rui.ColorPicker),
+//   - func(rui.Color, rui.Color),
+//   - func(rui.Color),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetColorChangedListeners(view View, subviewID ...string) []any {
+	return getTwoArgEventRawListeners[ColorPicker, Color](view, subviewID, ColorChangedEvent)
 }

columnLayout.go

@@ -249,13 +249,17 @@ func GetColumnSeparatorColor(view View, subviewID ...string) Color {
 
 // GetColumnFill returns a "column-fill" property value of the subview.
 // Returns one of next values: ColumnFillBalance (0) or ColumnFillAuto (1)
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetColumnFill(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, ColumnFill, ColumnFillBalance, true)
 }
 
 // IsColumnSpanAll returns a "column-span-all" property value of the subview.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func IsColumnSpanAll(view View, subviewID ...string) bool {
 	return boolStyledProperty(view, subviewID, ColumnSpanAll, false)
 }

columnSeparator.go

@@ -93,12 +93,12 @@ func NewColumnSeparator(style int, color Color, width SizeUnit) ColumnSeparatorP
 
 func (separator *columnSeparatorProperty) init() {
 	separator.dataProperty.init()
-	separator.normalize = normalizeVolumnSeparatorTag
+	separator.normalize = normalizeColumnSeparatorTag
 	separator.set = columnSeparatorSet
 	separator.supportedProperties = []PropertyName{Style, Width, ColorTag}
 }
 
-func normalizeVolumnSeparatorTag(tag PropertyName) PropertyName {
+func normalizeColumnSeparatorTag(tag PropertyName) PropertyName {
 	tag = defaultNormalize(tag)
 	switch tag {
 	case ColumnSeparatorStyle, "separator-style":

customView.go

@@ -98,8 +98,8 @@ func (customView *CustomViewData) SetParams(params Params) bool {
 }
 
 // SetChangeListener set the function to track the change of the View property
-func (customView *CustomViewData) SetChangeListener(tag PropertyName, listener func(View, PropertyName)) {
-	customView.superView.SetChangeListener(tag, listener)
+func (customView *CustomViewData) SetChangeListener(tag PropertyName, listener any) bool {
+	return customView.superView.SetChangeListener(tag, listener)
 }
 
 // Remove removes the property with name defined by the argument
@@ -292,15 +292,15 @@ func (customView *CustomViewData) ViewIndex(view View) int {
 	return -1
 }
 
-func (customView *CustomViewData) exscludeTags() []PropertyName {
+func (customView *CustomViewData) excludeTags() []PropertyName {
 	if customView.superView != nil {
-		exsclude := []PropertyName{}
+		exclude := []PropertyName{}
 		for tag, value := range customView.defaultParams {
 			if value == customView.superView.getRaw(tag) {
-				exsclude = append(exsclude, tag)
+				exclude = append(exclude, tag)
 			}
 		}
-		return exsclude
+		return exclude
 	}
 	return nil
 }
@@ -310,7 +310,7 @@ func (customView *CustomViewData) String() string {
 	if customView.superView != nil {
 		buffer := allocStringBuilder()
 		defer freeStringBuilder(buffer)
-		writeViewStyle(customView.tag, customView, buffer, "", customView.exscludeTags())
+		writeViewStyle(customView.tag, customView, buffer, "", customView.excludeTags())
 		return buffer.String()
 	}
 	return customView.tag + " { }"
@@ -352,3 +352,10 @@ func (customView *CustomViewData) LoadFile(file FileInfo, result func(FileInfo,
 		customView.superView.LoadFile(file, result)
 	}
 }
+
+func (customView *CustomViewData) binding() any {
+	if customView.superView != nil {
+		return customView.superView.binding()
+	}
+	return nil
+}

data.go

@@ -1,6 +1,9 @@
 package rui
 
 import (
+	"errors"
+	"fmt"
+	"slices"
 	"strings"
 	"unicode"
 )
@@ -47,16 +50,22 @@ type DataObject interface {
 
 	// ToParams create a params(map) representation of a data object
 	ToParams() Params
+
+	// PropertyByTag removes a data node corresponding to a property tag and returns it
+	RemovePropertyByTag(tag string) DataNode
 }
 
+// DataNodeType defines the type of DataNode
+type DataNodeType int
+
 // Constants which are used to describe a node type, see [DataNode]
 const (
 	// TextNode - node is the pair "tag - text value". Syntax: <tag> = <text>
-	TextNode = 0
+	TextNode DataNodeType = 0
 	// ObjectNode - node is the pair "tag - object". Syntax: <tag> = <object name>{...}
-	ObjectNode = 1
+	ObjectNode DataNodeType = 1
 	// ArrayNode - node is the pair "tag - object". Syntax: <tag> = [...]
-	ArrayNode = 2
+	ArrayNode DataNodeType = 2
 )
 
 // DataNode interface of a data node
@@ -65,7 +74,7 @@ type DataNode interface {
 	Tag() string
 
 	// Type returns a node type. Possible values are TextNode, ObjectNode and ArrayNode
-	Type() int
+	Type() DataNodeType
 
 	// Text returns node text
 	Text() string
@@ -158,6 +167,28 @@ func (object *dataObject) PropertyByTag(tag string) DataNode {
 	return nil
 }
 
+func (object *dataObject) RemovePropertyByTag(tag string) DataNode {
+	if object.property != nil {
+		for i, node := range object.property {
+			if node.Tag() == tag {
+				switch i {
+				case 0:
+					object.property = object.property[1:]
+
+				case len(object.property) - 1:
+					object.property = object.property[:len(object.property)-1]
+
+				default:
+					object.property = append(object.property[:i], object.property[i+1:]...)
+				}
+
+				return node
+			}
+		}
+	}
+	return nil
+}
+
 func (object *dataObject) PropertyValue(tag string) (string, bool) {
 	if node := object.PropertyByTag(tag); node != nil && node.Type() == TextNode {
 		return node.Text(), true
@@ -253,7 +284,7 @@ func (node *dataNode) Tag() string {
 	return node.tag
 }
 
-func (node *dataNode) Type() int {
+func (node *dataNode) Type() DataNodeType {
 	if node.array != nil {
 		return ArrayNode
 	}
@@ -314,411 +345,402 @@ func (node *dataNode) ArrayAsParams() []Params {
 	return result
 }
 
-// ParseDataText - parse text and return DataNode
-func ParseDataText(text string) DataObject {
+type dataParser struct {
+	data      []rune
+	size      int
+	pos       int
+	line      int
+	lineStart int
+}
 
-	if strings.ContainsAny(text, "\r") {
-		text = strings.Replace(text, "\r\n", "\n", -1)
-		text = strings.Replace(text, "\r", "\n", -1)
-	}
-	data := append([]rune(text), rune(0))
-	pos := 0
-	size := len(data) - 1
-	line := 1
-	lineStart := 0
+func (parser *dataParser) skipSpaces(skipNewLine bool) {
+	for parser.pos < parser.size {
+		switch parser.data[parser.pos] {
+		case '\n':
+			if !skipNewLine {
+				return
+			}
+			parser.line++
+			parser.lineStart = parser.pos + 1
 
-	skipSpaces := func(skipNewLine bool) {
-		for pos < size {
-			switch data[pos] {
-			case '\n':
-				if !skipNewLine {
-					return
-				}
-				line++
-				lineStart = pos + 1
-
-			case '/':
-				if pos+1 < size {
-					switch data[pos+1] {
-					case '/':
-						pos += 2
-						for pos < size && data[pos] != '\n' {
-							pos++
-						}
-						pos--
-
-					case '*':
-						pos += 3
-						for {
-							if pos >= size {
-								ErrorLog("Unexpected end of file")
-								return
-							}
-							if data[pos-1] == '*' && data[pos] == '/' {
-								break
-							}
-							if data[pos-1] == '\n' {
-								line++
-								lineStart = pos
-							}
-							pos++
-						}
-
-					default:
-						return
+		case '/':
+			if parser.pos+1 < parser.size {
+				switch parser.data[parser.pos+1] {
+				case '/':
+					parser.pos += 2
+					for parser.pos < parser.size && parser.data[parser.pos] != '\n' {
+						parser.pos++
 					}
-				}
+					parser.pos--
 
-			case ' ', '\t':
-				// do nothing
+				case '*':
+					parser.pos += 3
+					for {
+						if parser.pos >= parser.size {
+							ErrorLog("Unexpected end of file")
+							return
+						}
+						if parser.data[parser.pos-1] == '*' && parser.data[parser.pos] == '/' {
+							break
+						}
+						if parser.data[parser.pos-1] == '\n' {
+							parser.line++
+							parser.lineStart = parser.pos
+						}
+						parser.pos++
+					}
 
-			default:
-				if !unicode.IsSpace(data[pos]) {
+				default:
 					return
 				}
 			}
-			pos++
-		}
-	}
 
-	parseTag := func() (string, bool) {
-		skipSpaces(true)
-		startPos := pos
-		if data[pos] == '`' {
-			pos++
-			startPos++
-			for data[pos] != '`' {
-				pos++
-				if pos >= size {
-					ErrorLog("Unexpected end of text")
-					return string(data[startPos:size]), false
-				}
-			}
-			str := string(data[startPos:pos])
-			pos++
-			return str, true
-
-		} else if data[pos] == '\'' || data[pos] == '"' {
-
-			stopSymbol := data[pos]
-			pos++
-			startPos++
-			slash := false
-			for stopSymbol != data[pos] {
-				if data[pos] == '\\' {
-					pos += 2
-					slash = true
-				} else {
-					pos++
-				}
-				if pos >= size {
-					ErrorLog("Unexpected end of text")
-					return string(data[startPos:size]), false
-				}
-			}
-
-			if !slash {
-				str := string(data[startPos:pos])
-				pos++
-				skipSpaces(false)
-				return str, true
-			}
-
-			buffer := make([]rune, pos-startPos+1)
-			n1 := 0
-			n2 := startPos
-
-			invalidEscape := func() (string, bool) {
-				str := string(data[startPos:pos])
-				pos++
-				ErrorLogF("Invalid escape sequence in \"%s\" (position %d)", str, n2-2-startPos)
-				return str, false
-			}
-
-			for n2 < pos {
-				if data[n2] != '\\' {
-					buffer[n1] = data[n2]
-					n2++
-				} else {
-					n2 += 2
-					switch data[n2-1] {
-					case 'n':
-						buffer[n1] = '\n'
-
-					case 'r':
-						buffer[n1] = '\r'
-
-					case 't':
-						buffer[n1] = '\t'
-
-					case '"':
-						buffer[n1] = '"'
-
-					case '\'':
-						buffer[n1] = '\''
-
-					case '\\':
-						buffer[n1] = '\\'
-
-					case 'x', 'X':
-						if n2+2 > pos {
-							return invalidEscape()
-						}
-						x := 0
-						for range 2 {
-							ch := data[n2]
-							if ch >= '0' && ch <= '9' {
-								x = x*16 + int(ch-'0')
-							} else if ch >= 'a' && ch <= 'f' {
-								x = x*16 + int(ch-'a'+10)
-							} else if ch >= 'A' && ch <= 'F' {
-								x = x*16 + int(ch-'A'+10)
-							} else {
-								return invalidEscape()
-							}
-							n2++
-						}
-						buffer[n1] = rune(x)
-
-					case 'u', 'U':
-						if n2+4 > pos {
-							return invalidEscape()
-						}
-						x := 0
-						for range 4 {
-							ch := data[n2]
-							if ch >= '0' && ch <= '9' {
-								x = x*16 + int(ch-'0')
-							} else if ch >= 'a' && ch <= 'f' {
-								x = x*16 + int(ch-'a'+10)
-							} else if ch >= 'A' && ch <= 'F' {
-								x = x*16 + int(ch-'A'+10)
-							} else {
-								return invalidEscape()
-							}
-							n2++
-						}
-						buffer[n1] = rune(x)
-
-					default:
-						str := string(data[startPos:pos])
-						ErrorLogF("Invalid escape sequence in \"%s\" (position %d)", str, n2-2-startPos)
-						return str, false
-					}
-				}
-				n1++
-			}
-
-			pos++
-			skipSpaces(false)
-			return string(buffer[0:n1]), true
-		}
-
-		stopSymbol := func(symbol rune) bool {
-			if unicode.IsSpace(symbol) {
-				return true
-			}
-			for _, sym := range []rune{'=', '{', '}', '[', ']', ',', ' ', '\t', '\n', '\'', '"', '`', '/'} {
-				if sym == symbol {
-					return true
-				}
-			}
-			return false
-		}
-
-		for pos < size && !stopSymbol(data[pos]) {
-			pos++
-		}
-
-		endPos := pos
-		skipSpaces(false)
-		if startPos == endPos {
-			//ErrorLog("empty tag")
-			return "", true
-		}
-		return string(data[startPos:endPos]), true
-	}
-
-	var parseObject func(tag string) DataObject
-	var parseArray func() []DataValue
-
-	parseNode := func() DataNode {
-		var tag string
-		var ok bool
-
-		if tag, ok = parseTag(); !ok {
-			return nil
-		}
-
-		skipSpaces(true)
-		if data[pos] != '=' {
-			ErrorLogF("expected '=' after a tag name (line: %d, position: %d)", line, pos-lineStart)
-			return nil
-		}
-
-		pos++
-		skipSpaces(true)
-		switch data[pos] {
-		case '[':
-			node := new(dataNode)
-			node.tag = tag
-
-			if node.array = parseArray(); node.array == nil {
-				return nil
-			}
-			return node
-
-		case '{':
-			node := new(dataNode)
-			node.tag = tag
-			if node.value = parseObject("_"); node.value == nil {
-				return nil
-			}
-			return node
-
-		case '}', ']', '=':
-			ErrorLogF("Expected '[', '{' or a tag name after '=' (line: %d, position: %d)", line, pos-lineStart)
-			return nil
+		case ' ', '\t':
+			// do nothing
 
 		default:
-			var str string
-			if str, ok = parseTag(); !ok {
-				return nil
+			if !unicode.IsSpace(parser.data[parser.pos]) {
+				return
 			}
+		}
+		parser.pos++
+	}
+}
 
-			node := new(dataNode)
-			node.tag = tag
+func (parser *dataParser) parseTag() (string, error) {
+	parser.skipSpaces(true)
+	startPos := parser.pos
+	switch parser.data[parser.pos] {
+	case '`':
+		parser.pos++
+		startPos++
+		for parser.data[parser.pos] != '`' {
+			parser.pos++
+			if parser.pos >= parser.size {
+				return string(parser.data[startPos:parser.size]), errors.New("unexpected end of text")
+			}
+		}
+		str := string(parser.data[startPos:parser.pos])
+		parser.pos++
+		return str, nil
 
-			if data[pos] == '{' {
-				if node.value = parseObject(str); node.value == nil {
-					return nil
-				}
+	case '\'', '"':
+		stopSymbol := parser.data[parser.pos]
+		parser.pos++
+		startPos++
+		slash := false
+		for stopSymbol != parser.data[parser.pos] {
+			if parser.data[parser.pos] == '\\' {
+				parser.pos += 2
+				slash = true
 			} else {
-				val := new(dataStringValue)
-				val.value = str
-				node.value = val
+				parser.pos++
 			}
+			if parser.pos >= parser.size {
+				return string(parser.data[startPos:parser.size]), errors.New("unexpected end of text")
+			}
+		}
 
-			return node
+		if !slash {
+			str := string(parser.data[startPos:parser.pos])
+			parser.pos++
+			parser.skipSpaces(false)
+			return str, nil
+		}
+
+		buffer := make([]rune, parser.pos-startPos+1)
+		n1 := 0
+		n2 := startPos
+
+		invalidEscape := func() (string, error) {
+			str := string(parser.data[startPos:parser.pos])
+			parser.pos++
+			return str, fmt.Errorf(`invalid escape sequence in "%s" (position %d)`, str, n2-2-startPos)
+		}
+
+		for n2 < parser.pos {
+			if parser.data[n2] != '\\' {
+				buffer[n1] = parser.data[n2]
+				n2++
+			} else {
+				n2 += 2
+				switch parser.data[n2-1] {
+				case 'n':
+					buffer[n1] = '\n'
+
+				case 'r':
+					buffer[n1] = '\r'
+
+				case 't':
+					buffer[n1] = '\t'
+
+				case '"':
+					buffer[n1] = '"'
+
+				case '\'':
+					buffer[n1] = '\''
+
+				case '\\':
+					buffer[n1] = '\\'
+
+				case 'x', 'X':
+					if n2+2 > parser.pos {
+						return invalidEscape()
+					}
+					x := 0
+					for range 2 {
+						ch := parser.data[n2]
+						if ch >= '0' && ch <= '9' {
+							x = x*16 + int(ch-'0')
+						} else if ch >= 'a' && ch <= 'f' {
+							x = x*16 + int(ch-'a'+10)
+						} else if ch >= 'A' && ch <= 'F' {
+							x = x*16 + int(ch-'A'+10)
+						} else {
+							return invalidEscape()
+						}
+						n2++
+					}
+					buffer[n1] = rune(x)
+
+				case 'u', 'U':
+					if n2+4 > parser.pos {
+						return invalidEscape()
+					}
+					x := 0
+					for range 4 {
+						ch := parser.data[n2]
+						if ch >= '0' && ch <= '9' {
+							x = x*16 + int(ch-'0')
+						} else if ch >= 'a' && ch <= 'f' {
+							x = x*16 + int(ch-'a'+10)
+						} else if ch >= 'A' && ch <= 'F' {
+							x = x*16 + int(ch-'A'+10)
+						} else {
+							return invalidEscape()
+						}
+						n2++
+					}
+					buffer[n1] = rune(x)
+
+				default:
+					str := string(parser.data[startPos:parser.pos])
+					return str, fmt.Errorf(`invalid escape sequence in "%s" (position %d)`, str, n2-2-startPos)
+				}
+			}
+			n1++
+		}
+
+		parser.pos++
+		parser.skipSpaces(false)
+		return string(buffer[0:n1]), nil
+	}
+
+	for parser.pos < parser.size && !parser.stopSymbol(parser.data[parser.pos]) {
+		parser.pos++
+	}
+
+	endPos := parser.pos
+	parser.skipSpaces(false)
+	if startPos == endPos {
+		//ErrorLog("empty tag")
+		return "", nil
+	}
+	return string(parser.data[startPos:endPos]), nil
+}
+
+func (parser *dataParser) stopSymbol(symbol rune) bool {
+	return unicode.IsSpace(symbol) ||
+		slices.Contains([]rune{'=', '{', '}', '[', ']', ',', ' ', '\t', '\n', '\'', '"', '`', '/'}, symbol)
+}
+
+func (parser *dataParser) parseNode() (DataNode, error) {
+	var tag string
+	var err error
+
+	if tag, err = parser.parseTag(); err != nil {
+		return nil, err
+	}
+
+	parser.skipSpaces(true)
+	if parser.data[parser.pos] != '=' {
+		return nil, fmt.Errorf("expected '=' after a tag name (line: %d, position: %d)", parser.line, parser.pos-parser.lineStart)
+	}
+
+	parser.pos++
+	parser.skipSpaces(true)
+	switch parser.data[parser.pos] {
+	case '[':
+		node := new(dataNode)
+		node.tag = tag
+
+		if node.array, err = parser.parseArray(); err != nil {
+			return nil, err
+		}
+		return node, nil
+
+	case '{':
+		node := new(dataNode)
+		node.tag = tag
+		if node.value, err = parser.parseObject("_"); err != nil {
+			return nil, err
+		}
+		return node, nil
+
+	case '}', ']', '=':
+		return nil, fmt.Errorf(`expected '[', '{' or a tag name after '=' (line: %d, position: %d)`, parser.line, parser.pos-parser.lineStart)
+
+	default:
+		var str string
+		if str, err = parser.parseTag(); err != nil {
+			return nil, err
+		}
+
+		node := new(dataNode)
+		node.tag = tag
+
+		if parser.data[parser.pos] == '{' {
+			if node.value, err = parser.parseObject(str); err != nil {
+				return nil, err
+			}
+		} else {
+			val := new(dataStringValue)
+			val.value = str
+			node.value = val
+		}
+
+		return node, nil
+	}
+}
+
+func (parser *dataParser) parseObject(tag string) (DataObject, error) {
+	if parser.data[parser.pos] != '{' {
+		return nil, fmt.Errorf(`expected '{' (line: %d, position: %d)`, parser.line, parser.pos-parser.lineStart)
+	}
+	parser.pos++
+
+	obj := new(dataObject)
+	obj.tag = tag
+	obj.property = []DataNode{}
+
+	for parser.pos < parser.size {
+		parser.skipSpaces(true)
+		if parser.data[parser.pos] == '}' {
+			parser.pos++
+			parser.skipSpaces(false)
+			return obj, nil
+		}
+
+		node, err := parser.parseNode()
+		if err != nil {
+			return nil, err
+		}
+
+		obj.property = append(obj.property, node)
+		if parser.data[parser.pos] == '}' {
+			parser.pos++
+			parser.skipSpaces(true)
+			return obj, nil
+		} else if parser.data[parser.pos] != ',' && parser.data[parser.pos] != '\n' {
+			return nil, fmt.Errorf(`expected '}', '\n' or ',' (line: %d, position: %d)`, parser.line, parser.pos-parser.lineStart)
+		}
+
+		if parser.data[parser.pos] != '\n' {
+			parser.pos++
+		}
+
+		parser.skipSpaces(true)
+		for parser.data[parser.pos] == ',' {
+			parser.pos++
+			parser.skipSpaces(true)
 		}
 	}
 
-	parseObject = func(tag string) DataObject {
-		if data[pos] != '{' {
-			ErrorLogF("Expected '{' (line: %d, position: %d)", line, pos-lineStart)
-			return nil
-		}
-		pos++
+	return nil, errors.New("unexpected end of text")
+}
 
-		obj := new(dataObject)
-		obj.tag = tag
-		obj.property = []DataNode{}
+func (parser *dataParser) parseArray() ([]DataValue, error) {
+	parser.pos++
+	parser.skipSpaces(true)
 
-		for pos < size {
-			var node DataNode
+	array := []DataValue{}
 
-			skipSpaces(true)
-			if data[pos] == '}' {
-				pos++
-				skipSpaces(false)
-				return obj
-			}
-
-			if node = parseNode(); node == nil {
-				return nil
-			}
-			obj.property = append(obj.property, node)
-			if data[pos] == '}' {
-				pos++
-				skipSpaces(true)
-				return obj
-			} else if data[pos] != ',' && data[pos] != '\n' {
-				ErrorLogF(`Expected '}', '\n' or ',' (line: %d, position: %d)`, line, pos-lineStart)
-				return nil
-			}
-			if data[pos] != '\n' {
-				pos++
-			}
-			skipSpaces(true)
-			for data[pos] == ',' {
-				pos++
-				skipSpaces(true)
-			}
+	for parser.pos < parser.size {
+		parser.skipSpaces(true)
+		for parser.data[parser.pos] == ',' && parser.pos < parser.size {
+			parser.pos++
+			parser.skipSpaces(true)
 		}
 
-		ErrorLog("Unexpected end of text")
-		return nil
-	}
+		if parser.pos >= parser.size {
+			break
+		}
 
-	parseArray = func() []DataValue {
-		pos++
-		skipSpaces(true)
+		if parser.data[parser.pos] == ']' {
+			parser.pos++
+			parser.skipSpaces(true)
+			return array, nil
+		}
 
-		array := []DataValue{}
+		tag, err := parser.parseTag()
+		if err != nil {
+			return nil, err
+		}
 
-		for pos < size {
-			var tag string
-			var ok bool
-
-			skipSpaces(true)
-			for data[pos] == ',' && pos < size {
-				pos++
-				skipSpaces(true)
+		if parser.data[parser.pos] == '{' {
+			obj, err := parser.parseObject(tag)
+			if err != nil {
+				return nil, err
 			}
+			array = append(array, obj)
+		} else {
+			val := new(dataStringValue)
+			val.value = tag
+			array = append(array, val)
+		}
 
-			if pos >= size {
-				break
-			}
+		switch parser.data[parser.pos] {
+		case ']', ',', '\n':
 
+		default:
+			return nil, fmt.Errorf(`expected ']' or ',' (line: %d, position: %d)`, parser.line, parser.pos-parser.lineStart)
+		}
+
+		/*
 			if data[pos] == ']' {
-				pos++
-				skipSpaces(true)
-				return array
-			}
-
-			if tag, ok = parseTag(); !ok {
-				return nil
-			}
-
-			if data[pos] == '{' {
-				obj := parseObject(tag)
-				if obj == nil {
-					return nil
-				}
-				array = append(array, obj)
-			} else {
-				val := new(dataStringValue)
-				val.value = tag
-				array = append(array, val)
-			}
-
-			switch data[pos] {
-			case ']', ',', '\n':
-
-			default:
-				ErrorLogF("Expected ']' or ',' (line: %d, position: %d)", line, pos-lineStart)
-				return nil
-			}
-
-			/*
-				if data[pos] == ']' {
-					pos++
-					skipSpaces()
-					return array, nil
-				} else if data[pos] != ',' {
-					return nil, fmt.Errorf("Expected ']' or ',' (line: %d, position: %d)", line, pos-lineStart)
-				}
 				pos++
 				skipSpaces()
-			*/
-		}
-
-		ErrorLog("Unexpected end of text")
-		return nil
+				return array, nil
+			} else if data[pos] != ',' {
+				return nil, fmt.Errorf("Expected ']' or ',' (line: %d, position: %d)", line, pos-lineStart)
+			}
+			pos++
+			skipSpaces()
+		*/
 	}
 
-	if tag, ok := parseTag(); ok {
-		return parseObject(tag)
-	}
-	return nil
+	return nil, errors.New("unexpected end of text")
+}
+
+// ParseDataText - parse text and return DataNode
+func ParseDataText(text string) (DataObject, error) {
+
+	if strings.ContainsAny(text, "\r") {
+		text = strings.ReplaceAll(text, "\r\n", "\n")
+		text = strings.ReplaceAll(text, "\r", "\n")
+	}
+
+	parser := dataParser{
+		data:      append([]rune(text), rune(0)),
+		pos:       0,
+		line:      1,
+		lineStart: 0,
+	}
+	parser.size = len(parser.data) - 1
+
+	tag, err := parser.parseTag()
+	if err != nil {
+		return nil, err
+	}
+	return parser.parseObject(tag)
 }

dataList.go

@@ -312,7 +312,9 @@ func dataListHtmlProperties(view View, buffer *strings.Builder) {
 }
 
 // GetDataList returns the data list of an editor.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetDataList(view View, subviewID ...string) []string {
 	if view = getSubview(view, subviewID); view != nil {
 		return getDataListProperty(view)

data_test.go

@@ -6,10 +6,6 @@ import (
 
 func TestParseDataText(t *testing.T) {
 
-	SetErrorLog(func(text string) {
-		t.Error(text)
-	})
-
 	text := `obj1 {
 	key1 = val1,
 	key2=obj2{
@@ -27,8 +23,10 @@ func TestParseDataText(t *testing.T) {
 	key3 = "\n \t \\ \r \" ' \X4F\x4e \U01Ea",` +
 		"key4=`" + `\n \t \\ \r \" ' \x8F \UF80a` + "`\r}"
 
-	obj := ParseDataText(text)
-	if obj != nil {
+	obj, err := ParseDataText(text)
+	if err != nil {
+		t.Error(err)
+	} else {
 		if obj.Tag() != "obj1" {
 			t.Error(`obj.Tag() != "obj1"`)
 		}
@@ -75,7 +73,7 @@ func TestParseDataText(t *testing.T) {
 			t.Errorf(`obj.PropertyValue("key5") result: ("%s",%v)`, val, ok)
 		}
 
-		testKey := func(obj DataObject, index int, tag string, nodeType int) DataNode {
+		testKey := func(obj DataObject, index int, tag string, nodeType DataNodeType) DataNode {
 			key := obj.Property(index)
 			if key == nil {
 				t.Errorf(`%s.Property(%d) == nil`, obj.Tag(), index)
@@ -118,7 +116,7 @@ func TestParseDataText(t *testing.T) {
 
 				type testKeyData struct {
 					tag      string
-					nodeType int
+					nodeType DataNodeType
 				}
 
 				data := []testKeyData{
@@ -173,9 +171,6 @@ func TestParseDataText(t *testing.T) {
 		}
 	}
 
-	SetErrorLog(func(text string) {
-	})
-
 	failText := []string{
 		" ",
 		"obj[]",
@@ -204,7 +199,7 @@ func TestParseDataText(t *testing.T) {
 	}
 
 	for _, txt := range failText {
-		if obj := ParseDataText(txt); obj != nil {
+		if _, err := ParseDataText(txt); err == nil {
 			t.Errorf("result ParseDataText(\"%s\") must be fail", txt)
 		}
 	}

datePicker.go

@@ -274,7 +274,7 @@ func (picker *datePickerData) propertyChanged(tag PropertyName) {
 		date := GetDatePickerValue(picker)
 		session.callFunc("setInputValue", picker.htmlID(), date.Format(dateFormat))
 
-		if listeners := GetDateChangedListeners(picker); len(listeners) > 0 {
+		if listeners := getTwoArgEventListeners[DatePicker, time.Time](picker, nil, DateChangedEvent); len(listeners) > 0 {
 			oldDate := time.Now()
 			if value := picker.getRaw("old-date"); value != nil {
 				if date, ok := value.(time.Time); ok {
@@ -282,7 +282,7 @@ func (picker *datePickerData) propertyChanged(tag PropertyName) {
 				}
 			}
 			for _, listener := range listeners {
-				listener(picker, date, oldDate)
+				listener.Run(picker, date, oldDate)
 			}
 		}
 
@@ -348,11 +348,11 @@ func (picker *datePickerData) handleCommand(self View, command PropertyName, dat
 				oldValue := GetDatePickerValue(picker)
 				picker.properties[DatePickerValue] = value
 				if value != oldValue {
-					for _, listener := range GetDateChangedListeners(picker) {
-						listener(picker, value, oldValue)
+					for _, listener := range getTwoArgEventListeners[DatePicker, time.Time](picker, nil, DateChangedEvent) {
+						listener.Run(picker, value, oldValue)
 					}
 					if listener, ok := picker.changeListener[DatePickerValue]; ok {
-						listener(picker, DatePickerValue)
+						listener.Run(picker, DatePickerValue)
 					}
 				}
 			}
@@ -400,7 +400,9 @@ func getDateProperty(view View, mainTag, shortTag PropertyName) (time.Time, bool
 
 // GetDatePickerMin returns the min date of DatePicker subview and "true" as the second value if the min date is set,
 // "false" as the second value otherwise.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetDatePickerMin(view View, subviewID ...string) (time.Time, bool) {
 	if view = getSubview(view, subviewID); view != nil {
 		return getDateProperty(view, DatePickerMin, Min)
@@ -410,7 +412,9 @@ func GetDatePickerMin(view View, subviewID ...string) (time.Time, bool) {
 
 // GetDatePickerMax returns the max date of DatePicker subview and "true" as the second value if the min date is set,
 // "false" as the second value otherwise.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetDatePickerMax(view View, subviewID ...string) (time.Time, bool) {
 	if view = getSubview(view, subviewID); view != nil {
 		return getDateProperty(view, DatePickerMax, Max)
@@ -419,13 +423,17 @@ func GetDatePickerMax(view View, subviewID ...string) (time.Time, bool) {
 }
 
 // GetDatePickerStep returns the date changing step in days of DatePicker subview.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetDatePickerStep(view View, subviewID ...string) int {
 	return intStyledProperty(view, subviewID, DatePickerStep, 0)
 }
 
 // GetDatePickerValue returns the date of DatePicker subview.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetDatePickerValue(view View, subviewID ...string) time.Time {
 	if view = getSubview(view, subviewID); view == nil {
 		return time.Now()
@@ -436,7 +444,18 @@ func GetDatePickerValue(view View, subviewID ...string) time.Time {
 
 // GetDateChangedListeners returns the DateChangedListener list of an DatePicker subview.
 // If there are no listeners then the empty list is returned
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetDateChangedListeners(view View, subviewID ...string) []func(DatePicker, time.Time, time.Time) {
-	return getTwoArgEventListeners[DatePicker, time.Time](view, subviewID, DateChangedEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.DatePicker, time.Time, time.Time),
+//   - func(rui.DatePicker, time.Time),
+//   - func(rui.DatePicker),
+//   - func(time.Time, time.Time),
+//   - func(time.Time),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetDateChangedListeners(view View, subviewID ...string) []any {
+	return getTwoArgEventRawListeners[DatePicker, time.Time](view, subviewID, DateChangedEvent)
 }

detailsView.go

@@ -92,7 +92,7 @@ func (detailsView *detailsViewData) setFunc(tag PropertyName, value any) []Prope
 			value.setParentID(detailsView.htmlID())
 
 		case DataObject:
-			if view := CreateViewFromObject(detailsView.Session(), value); view != nil {
+			if view := CreateViewFromObject(detailsView.Session(), value, nil); view != nil {
 				detailsView.setRaw(Summary, view)
 				view.setParentID(detailsView.htmlID())
 			} else {
@@ -193,7 +193,7 @@ func (detailsView *detailsViewData) handleCommand(self View, command PropertyNam
 		if n, ok := dataIntProperty(data, "open"); ok {
 			detailsView.properties[Expanded] = (n != 0)
 			if listener, ok := detailsView.changeListener[Expanded]; ok {
-				listener(detailsView, Expanded)
+				listener.Run(detailsView, Expanded)
 			}
 		}
 		return true
@@ -202,7 +202,9 @@ func (detailsView *detailsViewData) handleCommand(self View, command PropertyNam
 }
 
 // GetDetailsSummary returns a value of the Summary property of DetailsView.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetDetailsSummary(view View, subviewID ...string) View {
 	if view = getSubview(view, subviewID); view != nil {
 		if value := view.Get(Summary); value != nil {
@@ -219,13 +221,17 @@ func GetDetailsSummary(view View, subviewID ...string) View {
 }
 
 // IsDetailsExpanded returns a value of the Expanded property of DetailsView.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func IsDetailsExpanded(view View, subviewID ...string) bool {
 	return boolStyledProperty(view, subviewID, Expanded, false)
 }
 
 // IsDetailsExpanded returns a value of the HideSummaryMarker property of DetailsView.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func IsSummaryMarkerHidden(view View, subviewID ...string) bool {
 	return boolStyledProperty(view, subviewID, HideSummaryMarker, false)
 }

dragAndDrop.go

@@ -49,7 +49,7 @@ const (
 	// Supported types: int, string.
 	//
 	// Values:
-	//   - 0 (DropEffectUndefined) or "undefined" - The property value is not defined (defaut value).
+	//   - 0 (DropEffectUndefined) or "undefined" - The property value is not defined (default value).
 	//   - 1 (DropEffectCopy) or "copy" - A copy of the source item may be made at the new location.
 	//   - 2 (DropEffectMove) or "move" - An item may be moved to a new location.
 	//   - 4 (DropEffectLink) or "link" - A link may be established to the source at the new location.
@@ -68,7 +68,7 @@ const (
 	// Supported types: int, string.
 	//
 	// Values:
-	//   - 0 (DropEffectUndefined) or "undefined" - The property value is not defined (defaut value). Equivalent to DropEffectAll
+	//   - 0 (DropEffectUndefined) or "undefined" - The property value is not defined (default value). Equivalent to DropEffectAll
 	//   - 1 (DropEffectCopy) or "copy" - A copy of the source item may be made at the new location.
 	//   - 2 (DropEffectMove) or "move" - An item may be moved to a new location.
 	//   - 3 (DropEffectLink) or "link" - A link may be established to the source at the new location.
@@ -84,7 +84,16 @@ const (
 	// Fired when the user starts dragging an element or text selection.
 	//
 	// General listener format:
+	//  func(view rui.View, event rui.DragAndDropEvent).
 	//
+	// where:
+	//   - view - Interface of a view which generated this event,
+	//   - event - event parameters.
+	//
+	// Allowed listener formats:
+	//  func(view rui.View)
+	//  func(rui.DragAndDropEvent)
+	//  func()
 	DragStartEvent PropertyName = "drag-start-event"
 
 	// DragEndEvent is the constant for "drag-end-event" property tag.
@@ -93,7 +102,16 @@ const (
 	// Fired when a drag operation ends (by releasing a mouse button or hitting the escape key).
 	//
 	// General listener format:
+	//  func(view rui.View, event rui.DragAndDropEvent).
 	//
+	// where:
+	//   - view - Interface of a view which generated this event,
+	//   - event - event parameters.
+	//
+	// Allowed listener formats:
+	//  func(view rui.View)
+	//  func(rui.DragAndDropEvent)
+	//  func()
 	DragEndEvent PropertyName = "drag-end-event"
 
 	// DragEnterEvent is the constant for "drag-enter-event" property tag.
@@ -102,7 +120,16 @@ const (
 	// Fired when a dragged element or text selection enters a valid drop target.
 	//
 	// General listener format:
+	//  func(view rui.View, event rui.DragAndDropEvent).
 	//
+	// where:
+	//   - view - Interface of a view which generated this event,
+	//   - event - event parameters.
+	//
+	// Allowed listener formats:
+	//  func(view rui.View)
+	//  func(rui.DragAndDropEvent)
+	//  func()
 	DragEnterEvent PropertyName = "drag-enter-event"
 
 	// DragLeaveEvent is the constant for "drag-leave-event" property tag.
@@ -111,7 +138,16 @@ const (
 	// Fired when a dragged element or text selection leaves a valid drop target.
 	//
 	// General listener format:
+	//  func(view rui.View, event rui.DragAndDropEvent).
 	//
+	// where:
+	//   - view - Interface of a view which generated this event,
+	//   - event - event parameters.
+	//
+	// Allowed listener formats:
+	//  func(view rui.View)
+	//  func(rui.DragAndDropEvent)
+	//  func()
 	DragLeaveEvent PropertyName = "drag-leave-event"
 
 	// DragOverEvent is the constant for "drag-over-event" property tag.
@@ -120,7 +156,16 @@ const (
 	// Fired when an element or text selection is being dragged over a valid drop target (every few hundred milliseconds).
 	//
 	// General listener format:
+	//  func(view rui.View, event rui.DragAndDropEvent).
 	//
+	// where:
+	//   - view - Interface of a view which generated this event,
+	//   - event - event parameters.
+	//
+	// Allowed listener formats:
+	//  func(view rui.View)
+	//  func(rui.DragAndDropEvent)
+	//  func()
 	DragOverEvent PropertyName = "drag-over-event"
 
 	// DropEvent is the constant for "drop-event" property tag.
@@ -129,7 +174,16 @@ const (
 	// Fired when an element or text selection is dropped on a valid drop target.
 	//
 	// General listener format:
+	//  func(view rui.View, event rui.DragAndDropEvent).
 	//
+	// where:
+	//   - view - Interface of a view which generated this event,
+	//   - event - event parameters.
+	//
+	// Allowed listener formats:
+	//  func(view rui.View)
+	//  func(rui.DragAndDropEvent)
+	//  func()
 	DropEvent PropertyName = "drop-event"
 
 	// DropEffectUndefined - the value of the "drop-effect" and "drop-effect-allowed" properties: the value is not defined (default value).
@@ -156,7 +210,7 @@ const (
 	// DropEffectLinkMove - the value of the "drop-effect-allowed" property: a link or move operation is permitted.
 	DropEffectLinkMove = DropEffectLink + DropEffectMove
 
-	// DropEffectAll - the value of the "drop-effect-allowed" property: all operations (copy, move, and link) are permitted (defaut value).
+	// DropEffectAll - the value of the "drop-effect-allowed" property: all operations (copy, move, and link) are permitted (default value).
 	DropEffectAll = DropEffectCopy + DropEffectMove + DropEffectLink
 )
 
@@ -336,7 +390,7 @@ func handleDragAndDropEvents(view View, tag PropertyName, data DataObject) {
 		event.init(view.Session(), data)
 
 		for _, listener := range listeners {
-			listener(view, event)
+			listener.Run(view, event)
 		}
 	}
 }
@@ -408,17 +462,17 @@ func dragAndDropHtml(view View, buffer *strings.Builder) {
 
 	if f := GetDragImageXOffset(view); f != 0 {
 		buffer.WriteString(` data-drag-image-x="`)
-		buffer.WriteString(fmt.Sprintf("%g", f))
+		fmt.Fprintf(buffer, "%g", f)
 		buffer.WriteString(`" `)
 	}
 
 	if f := GetDragImageYOffset(view); f != 0 {
 		buffer.WriteString(` data-drag-image-y="`)
-		buffer.WriteString(fmt.Sprintf("%g", f))
+		fmt.Fprintf(buffer, "%g", f)
 		buffer.WriteString(`" `)
 	}
 
-	effects := []string{"undifined", "copy", "move", "copyMove", "link", "copyLink", "linkMove", "all"}
+	effects := []string{"undefined", "copy", "move", "copyMove", "link", "copyLink", "linkMove", "all"}
 	if n := GetDropEffectAllowed(view); n > 0 && n < len(effects) {
 		buffer.WriteString(` data-drop-effect-allowed="`)
 		buffer.WriteString(effects[n])
@@ -434,41 +488,99 @@ func (view *viewData) LoadFile(file FileInfo, result func(FileInfo, []byte)) {
 }
 
 // GetDragStartEventListeners returns the "drag-start-event" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetDragStartEventListeners(view View, subviewID ...string) []func(View, DragAndDropEvent) {
-	return getOneArgEventListeners[View, DragAndDropEvent](view, subviewID, DragStartEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.View, rui.DragAndDropEvent),
+//   - func(rui.View),
+//   - func(rui.DragAndDropEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetDragStartEventListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, DragAndDropEvent](view, subviewID, DragStartEvent)
 }
 
 // GetDragEndEventListeners returns the "drag-end-event" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetDragEndEventListeners(view View, subviewID ...string) []func(View, DragAndDropEvent) {
-	return getOneArgEventListeners[View, DragAndDropEvent](view, subviewID, DragEndEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.View, rui.DragAndDropEvent),
+//   - func(rui.View),
+//   - func(rui.DragAndDropEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetDragEndEventListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, DragAndDropEvent](view, subviewID, DragEndEvent)
 }
 
 // GetDragEnterEventListeners returns the "drag-enter-event" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetDragEnterEventListeners(view View, subviewID ...string) []func(View, DragAndDropEvent) {
-	return getOneArgEventListeners[View, DragAndDropEvent](view, subviewID, DragEnterEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.View, rui.DragAndDropEvent),
+//   - func(rui.View),
+//   - func(rui.DragAndDropEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetDragEnterEventListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, DragAndDropEvent](view, subviewID, DragEnterEvent)
 }
 
 // GetDragLeaveEventListeners returns the "drag-leave-event" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetDragLeaveEventListeners(view View, subviewID ...string) []func(View, DragAndDropEvent) {
-	return getOneArgEventListeners[View, DragAndDropEvent](view, subviewID, DragLeaveEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.View, rui.DragAndDropEvent),
+//   - func(rui.View),
+//   - func(rui.DragAndDropEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetDragLeaveEventListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, DragAndDropEvent](view, subviewID, DragLeaveEvent)
 }
 
 // GetDragOverEventListeners returns the "drag-over-event" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetDragOverEventListeners(view View, subviewID ...string) []func(View, DragAndDropEvent) {
-	return getOneArgEventListeners[View, DragAndDropEvent](view, subviewID, DragOverEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.View, rui.DragAndDropEvent),
+//   - func(rui.View),
+//   - func(rui.DragAndDropEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetDragOverEventListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, DragAndDropEvent](view, subviewID, DragOverEvent)
 }
 
 // GetDropEventListeners returns the "drag-start-event" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetDropEventListeners(view View, subviewID ...string) []func(View, DragAndDropEvent) {
-	return getOneArgEventListeners[View, DragAndDropEvent](view, subviewID, DropEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.View, rui.DragAndDropEvent),
+//   - func(rui.View),
+//   - func(rui.DragAndDropEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetDropEventListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, DragAndDropEvent](view, subviewID, DropEvent)
 }
 
+// GetDropEventListeners returns the "drag-data" data.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetDragData(view View, subviewID ...string) map[string]string {
 	result := map[string]string{}
 	if view = getSubview(view, subviewID); view != nil {
@@ -483,7 +595,9 @@ func GetDragData(view View, subviewID ...string) map[string]string {
 }
 
 // GetDragImage returns the drag feedback image.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetDragImage(view View, subviewID ...string) string {
 	if view = getSubview(view, subviewID); view != nil {
 		value := view.getRaw(DragImage)
@@ -508,13 +622,17 @@ func GetDragImage(view View, subviewID ...string) string {
 }
 
 // GetDragImageXOffset returns the horizontal offset in pixels within the drag feedback image.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetDragImageXOffset(view View, subviewID ...string) float64 {
 	return floatStyledProperty(view, subviewID, DragImageXOffset, 0)
 }
 
 // GetDragImageYOffset returns the vertical offset in pixels within the drag feedback image.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetDragImageYOffset(view View, subviewID ...string) float64 {
 	return floatStyledProperty(view, subviewID, DragImageYOffset, 0)
 }
@@ -529,7 +647,8 @@ func GetDragImageYOffset(view View, subviewID ...string) float64 {
 //   - 2 (DropEffectMove) - An item may be moved to a new location.
 //   - 4 (DropEffectLink) - A link may be established to the source at the new location.
 //
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetDropEffect(view View, subviewID ...string) int {
 	if view = getSubview(view, subviewID); view != nil {
 		value := view.getRaw(DropEffect)
@@ -573,7 +692,8 @@ func GetDropEffect(view View, subviewID ...string) int {
 //   - 6 (DropEffectLinkMove) - A link or move operation is permitted.
 //   - 7 (DropEffectAll) - All operations are permitted.
 //
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetDropEffectAllowed(view View, subviewID ...string) int {
 	if view = getSubview(view, subviewID); view != nil {
 		value := view.getRaw(DropEffectAllowed)

dropDownList.go

@@ -104,8 +104,8 @@ func (list *dropDownListData) propertyChanged(tag PropertyName) {
 		list.Session().callFunc("selectDropDownListItem", list.htmlID(), current)
 
 		oldCurrent, _ := intProperty(list, "old-current", list.Session(), -1)
-		for _, listener := range GetDropDownListeners(list) {
-			listener(list, current, oldCurrent)
+		for _, listener := range getTwoArgEventListeners[DropDownList, int](list, nil, DropDownEvent) {
+			listener.Run(list, current, oldCurrent)
 		}
 
 	default:
@@ -245,11 +245,11 @@ func (list *dropDownListData) handleCommand(self View, command PropertyName, dat
 				if GetCurrent(list) != number && number >= 0 && number < len(items) {
 					old := GetCurrent(list)
 					list.properties[Current] = number
-					for _, listener := range GetDropDownListeners(list) {
-						listener(list, number, old)
+					for _, listener := range getTwoArgEventListeners[DropDownList, int](list, nil, DropDownEvent) {
+						listener.Run(list, number, old)
 					}
 					if listener, ok := list.changeListener[Current]; ok {
-						listener(list, Current)
+						listener.Run(list, Current)
 					}
 				}
 			} else {
@@ -264,13 +264,26 @@ func (list *dropDownListData) handleCommand(self View, command PropertyName, dat
 }
 
 // GetDropDownListeners returns the "drop-down-event" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetDropDownListeners(view View, subviewID ...string) []func(DropDownList, int, int) {
-	return getTwoArgEventListeners[DropDownList, int](view, subviewID, DropDownEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.DropDownList, int, int),
+//   - func(rui.DropDownList, int),
+//   - func(rui.DropDownList),
+//   - func(int, int),
+//   - func(int),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetDropDownListeners(view View, subviewID ...string) []any {
+	return getTwoArgEventRawListeners[DropDownList, int](view, subviewID, DropDownEvent)
 }
 
 // GetDropDownItems return the DropDownList items list.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetDropDownItems(view View, subviewID ...string) []string {
 	if view = getSubview(view, subviewID); view != nil {
 		if value := view.Get(Items); value != nil {
@@ -313,14 +326,18 @@ func getIndicesArray(view View, tag PropertyName) []int {
 }
 
 // GetDropDownDisabledItems return an array of disabled(non selectable) items indices of DropDownList.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetDropDownDisabledItems(view View, subviewID ...string) []int {
 	view = getSubview(view, subviewID)
 	return getIndicesArray(view, DisabledItems)
 }
 
 // GetDropDownItemSeparators return an array of indices of DropDownList items after which a separator should be added.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetDropDownItemSeparators(view View, subviewID ...string) []int {
 	view = getSubview(view, subviewID)
 	return getIndicesArray(view, ItemSeparators)

editView.go

@@ -268,11 +268,11 @@ func (edit *editViewData) AppendText(text string) {
 }
 
 func (edit *editViewData) textChanged(newText, oldText string) {
-	for _, listener := range GetTextChangedListeners(edit) {
-		listener(edit, newText, oldText)
+	for _, listener := range getTwoArgEventListeners[EditView, string](edit, nil, EditTextChangedEvent) {
+		listener.Run(edit, newText, oldText)
 	}
 	if listener, ok := edit.changeListener[Text]; ok {
-		listener(edit, Text)
+		listener.Run(edit, Text)
 	}
 }
 
@@ -451,26 +451,43 @@ func IsReadOnly(view View, subviewID ...string) bool {
 }
 
 // IsSpellcheck returns a value of the Spellcheck property of EditView.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func IsSpellcheck(view View, subviewID ...string) bool {
 	return boolStyledProperty(view, subviewID, Spellcheck, false)
 }
 
 // GetTextChangedListeners returns the TextChangedListener list of an EditView or MultiLineEditView subview.
 // If there are no listeners then the empty list is returned
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetTextChangedListeners(view View, subviewID ...string) []func(EditView, string, string) {
-	return getTwoArgEventListeners[EditView, string](view, subviewID, EditTextChangedEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.EditView, string, string),
+//   - func(rui.EditView, string),
+//   - func(rui.EditView),
+//   - func(string, string),
+//   - func(string),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetTextChangedListeners(view View, subviewID ...string) []any {
+	return getTwoArgEventRawListeners[EditView, string](view, subviewID, EditTextChangedEvent)
 }
 
 // GetEditViewType returns a value of the Type property of EditView.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetEditViewType(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, EditViewType, SingleLineText, false)
 }
 
 // GetEditViewPattern returns a value of the Pattern property of EditView.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetEditViewPattern(view View, subviewID ...string) string {
 	if view = getSubview(view, subviewID); view != nil {
 		if pattern, ok := stringProperty(view, EditViewPattern, view.Session()); ok {
@@ -488,13 +505,17 @@ func GetEditViewPattern(view View, subviewID ...string) string {
 }
 
 // IsEditViewWrap returns a value of the EditWrap property of MultiLineEditView.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func IsEditViewWrap(view View, subviewID ...string) bool {
 	return boolStyledProperty(view, subviewID, EditWrap, false)
 }
 
 // AppendEditText appends the text to the EditView content.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func AppendEditText(view View, subviewID string, text string) {
 	if subviewID != "" {
 		if edit := EditViewByID(view, subviewID); edit != nil {
@@ -509,7 +530,9 @@ func AppendEditText(view View, subviewID string, text string) {
 }
 
 // GetCaretColor returns the color of the text input caret.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetCaretColor(view View, subviewID ...string) Color {
 	return colorStyledProperty(view, subviewID, CaretColor, false)
 }

events.go

@@ -1,6 +1,9 @@
 package rui
 
-import "strings"
+import (
+	"reflect"
+	"strings"
+)
 
 var eventJsFunc = map[PropertyName]struct{ jsEvent, jsFunc string }{
 	FocusEvent:              {jsEvent: "onfocus", jsFunc: "focusEvent"},
@@ -38,469 +41,14 @@ var eventJsFunc = map[PropertyName]struct{ jsEvent, jsFunc string }{
 	DragLeaveEvent:          {jsEvent: "ondragleave", jsFunc: "dragLeaveEvent"},
 }
 
-func valueToNoArgEventListeners[V any](value any) ([]func(V), bool) {
-	if value == nil {
-		return nil, true
-	}
-
-	switch value := value.(type) {
-	case func(V):
-		return []func(V){value}, true
-
-	case func():
-		fn := func(V) {
-			value()
-		}
-		return []func(V){fn}, true
-
-	case []func(V):
-		if len(value) == 0 {
-			return nil, true
-		}
-		for _, fn := range value {
-			if fn == nil {
-				return nil, false
-			}
-		}
-		return value, true
-
-	case []func():
-		count := len(value)
-		if count == 0 {
-			return nil, true
-		}
-		listeners := make([]func(V), count)
-		for i, v := range value {
-			if v == nil {
-				return nil, false
-			}
-			listeners[i] = func(V) {
-				v()
-			}
-		}
-		return listeners, true
-
-	case []any:
-		count := len(value)
-		if count == 0 {
-			return nil, true
-		}
-		listeners := make([]func(V), count)
-		for i, v := range value {
-			if v == nil {
-				return nil, false
-			}
-			switch v := v.(type) {
-			case func(V):
-				listeners[i] = v
-
-			case func():
-				listeners[i] = func(V) {
-					v()
-				}
-
-			default:
-				return nil, false
-			}
-		}
-		return listeners, true
-	}
-
-	return nil, false
-}
-
-func valueToOneArgEventListeners[V View, E any](value any) ([]func(V, E), bool) {
-	if value == nil {
-		return nil, true
-	}
-
-	switch value := value.(type) {
-	case func(V, E):
-		return []func(V, E){value}, true
-
-	case func(E):
-		fn := func(_ V, event E) {
-			value(event)
-		}
-		return []func(V, E){fn}, true
-
-	case func(V):
-		fn := func(view V, _ E) {
-			value(view)
-		}
-		return []func(V, E){fn}, true
-
-	case func():
-		fn := func(V, E) {
-			value()
-		}
-		return []func(V, E){fn}, true
-
-	case []func(V, E):
-		if len(value) == 0 {
-			return nil, true
-		}
-		for _, fn := range value {
-			if fn == nil {
-				return nil, false
-			}
-		}
-		return value, true
-
-	case []func(E):
-		count := len(value)
-		if count == 0 {
-			return nil, true
-		}
-		listeners := make([]func(V, E), count)
-		for i, v := range value {
-			if v == nil {
-				return nil, false
-			}
-			listeners[i] = func(_ V, event E) {
-				v(event)
-			}
-		}
-		return listeners, true
-
-	case []func(V):
-		count := len(value)
-		if count == 0 {
-			return nil, true
-		}
-		listeners := make([]func(V, E), count)
-		for i, v := range value {
-			if v == nil {
-				return nil, false
-			}
-			listeners[i] = func(view V, _ E) {
-				v(view)
-			}
-		}
-		return listeners, true
-
-	case []func():
-		count := len(value)
-		if count == 0 {
-			return nil, true
-		}
-		listeners := make([]func(V, E), count)
-		for i, v := range value {
-			if v == nil {
-				return nil, false
-			}
-			listeners[i] = func(V, E) {
-				v()
-			}
-		}
-		return listeners, true
-
-	case []any:
-		count := len(value)
-		if count == 0 {
-			return nil, true
-		}
-		listeners := make([]func(V, E), count)
-		for i, v := range value {
-			if v == nil {
-				return nil, false
-			}
-			switch v := v.(type) {
-			case func(V, E):
-				listeners[i] = v
-
-			case func(E):
-				listeners[i] = func(_ V, event E) {
-					v(event)
-				}
-
-			case func(V):
-				listeners[i] = func(view V, _ E) {
-					v(view)
-				}
-
-			case func():
-				listeners[i] = func(V, E) {
-					v()
-				}
-
-			default:
-				return nil, false
-			}
-		}
-		return listeners, true
-	}
-
-	return nil, false
-}
-
-func valueToTwoArgEventListeners[V View, E any](value any) ([]func(V, E, E), bool) {
-	if value == nil {
-		return nil, true
-	}
-
-	switch value := value.(type) {
-	case func(V, E, E):
-		return []func(V, E, E){value}, true
-
-	case func(V, E):
-		fn := func(v V, val, _ E) {
-			value(v, val)
-		}
-		return []func(V, E, E){fn}, true
-
-	case func(E, E):
-		fn := func(_ V, val, old E) {
-			value(val, old)
-		}
-		return []func(V, E, E){fn}, true
-
-	case func(E):
-		fn := func(_ V, val, _ E) {
-			value(val)
-		}
-		return []func(V, E, E){fn}, true
-
-	case func(V):
-		fn := func(v V, _, _ E) {
-			value(v)
-		}
-		return []func(V, E, E){fn}, true
-
-	case func():
-		fn := func(V, E, E) {
-			value()
-		}
-		return []func(V, E, E){fn}, true
-
-	case []func(V, E, E):
-		if len(value) == 0 {
-			return nil, true
-		}
-		for _, fn := range value {
-			if fn == nil {
-				return nil, false
-			}
-		}
-		return value, true
-
-	case []func(V, E):
-		count := len(value)
-		if count == 0 {
-			return nil, true
-		}
-		listeners := make([]func(V, E, E), count)
-		for i, fn := range value {
-			if fn == nil {
-				return nil, false
-			}
-			listeners[i] = func(view V, val, _ E) {
-				fn(view, val)
-			}
-		}
-		return listeners, true
-
-	case []func(E):
-		count := len(value)
-		if count == 0 {
-			return nil, true
-		}
-		listeners := make([]func(V, E, E), count)
-		for i, fn := range value {
-			if fn == nil {
-				return nil, false
-			}
-			listeners[i] = func(_ V, val, _ E) {
-				fn(val)
-			}
-		}
-		return listeners, true
-
-	case []func(E, E):
-		count := len(value)
-		if count == 0 {
-			return nil, true
-		}
-		listeners := make([]func(V, E, E), count)
-		for i, fn := range value {
-			if fn == nil {
-				return nil, false
-			}
-			listeners[i] = func(_ V, val, old E) {
-				fn(val, old)
-			}
-		}
-		return listeners, true
-
-	case []func(V):
-		count := len(value)
-		if count == 0 {
-			return nil, true
-		}
-		listeners := make([]func(V, E, E), count)
-		for i, fn := range value {
-			if fn == nil {
-				return nil, false
-			}
-			listeners[i] = func(view V, _, _ E) {
-				fn(view)
-			}
-		}
-		return listeners, true
-
-	case []func():
-		count := len(value)
-		if count == 0 {
-			return nil, true
-		}
-		listeners := make([]func(V, E, E), count)
-		for i, fn := range value {
-			if fn == nil {
-				return nil, false
-			}
-			listeners[i] = func(V, E, E) {
-				fn()
-			}
-		}
-		return listeners, true
-
-	case []any:
-		count := len(value)
-		if count == 0 {
-			return nil, true
-		}
-		listeners := make([]func(V, E, E), count)
-		for i, v := range value {
-			if v == nil {
-				return nil, false
-			}
-			switch fn := v.(type) {
-			case func(V, E, E):
-				listeners[i] = fn
-
-			case func(V, E):
-				listeners[i] = func(view V, val, _ E) {
-					fn(view, val)
-				}
-
-			case func(E, E):
-				listeners[i] = func(_ V, val, old E) {
-					fn(val, old)
-				}
-
-			case func(E):
-				listeners[i] = func(_ V, val, _ E) {
-					fn(val)
-				}
-
-			case func(V):
-				listeners[i] = func(view V, _, _ E) {
-					fn(view)
-				}
-
-			case func():
-				listeners[i] = func(V, E, E) {
-					fn()
-				}
-
-			default:
-				return nil, false
-			}
-		}
-		return listeners, true
-	}
-
-	return nil, false
-}
-
-func getNoArgEventListeners[V View](view View, subviewID []string, tag PropertyName) []func(V) {
-	if view = getSubview(view, subviewID); view != nil {
-		if value := view.Get(tag); value != nil {
-			if result, ok := value.([]func(V)); ok {
-				return result
-			}
-		}
-	}
-	return []func(V){}
-}
-
-func getOneArgEventListeners[V View, E any](view View, subviewID []string, tag PropertyName) []func(V, E) {
-	if view = getSubview(view, subviewID); view != nil {
-		if value := view.Get(tag); value != nil {
-			if result, ok := value.([]func(V, E)); ok {
-				return result
-			}
-		}
-	}
-	return []func(V, E){}
-}
-
-func getTwoArgEventListeners[V View, E any](view View, subviewID []string, tag PropertyName) []func(V, E, E) {
-	if view = getSubview(view, subviewID); view != nil {
-		if value := view.Get(tag); value != nil {
-			if result, ok := value.([]func(V, E, E)); ok {
-				return result
-			}
-		}
-	}
-	return []func(V, E, E){}
-}
-
-func setNoArgEventListener[V View](properties Properties, tag PropertyName, value any) []PropertyName {
-	if listeners, ok := valueToNoArgEventListeners[V](value); ok {
-		if len(listeners) > 0 {
-			properties.setRaw(tag, listeners)
-		} else if properties.getRaw(tag) != nil {
-			properties.setRaw(tag, nil)
-		} else {
-			return []PropertyName{}
-		}
-		return []PropertyName{tag}
-	}
-	notCompatibleType(tag, value)
-	return nil
-}
-
-func setOneArgEventListener[V View, T any](properties Properties, tag PropertyName, value any) []PropertyName {
-	if listeners, ok := valueToOneArgEventListeners[V, T](value); ok {
-		if len(listeners) > 0 {
-			properties.setRaw(tag, listeners)
-		} else if properties.getRaw(tag) != nil {
-			properties.setRaw(tag, nil)
-		} else {
-			return []PropertyName{}
-		}
-		return []PropertyName{tag}
-	}
-	notCompatibleType(tag, value)
-	return nil
-}
-
-func setTwoArgEventListener[V View, T any](properties Properties, tag PropertyName, value any) []PropertyName {
-	listeners, ok := valueToTwoArgEventListeners[V, T](value)
-	if !ok {
-		notCompatibleType(tag, value)
-		return nil
-	} else if len(listeners) > 0 {
-		properties.setRaw(tag, listeners)
-	} else if properties.getRaw(tag) != nil {
-		properties.setRaw(tag, nil)
-	} else {
-		return []PropertyName{}
-	}
-	return []PropertyName{tag}
-}
-
 func viewEventsHtml[T any](view View, events []PropertyName, buffer *strings.Builder) {
 	for _, tag := range events {
-		if value := view.getRaw(tag); value != nil {
-			if js, ok := eventJsFunc[tag]; ok {
-				if listeners, ok := value.([]func(View, T)); ok && len(listeners) > 0 {
-					buffer.WriteString(js.jsEvent)
-					buffer.WriteString(`="`)
-					buffer.WriteString(js.jsFunc)
-					buffer.WriteString(`(this, event)" `)
-				}
+		if js, ok := eventJsFunc[tag]; ok {
+			if value := getOneArgEventListeners[View, T](view, nil, tag); len(value) > 0 {
+				buffer.WriteString(js.jsEvent)
+				buffer.WriteString(`="`)
+				buffer.WriteString(js.jsFunc)
+				buffer.WriteString(`(this, event)" `)
 			}
 		}
 	}
@@ -518,3 +66,197 @@ func updateEventListenerHtml(view View, tag PropertyName) {
 		}
 	}
 }
+
+type noArgListener[V View] interface {
+	Run(V)
+	rawListener() any
+}
+
+type noArgListener0[V View] struct {
+	fn func()
+}
+
+type noArgListenerV[V View] struct {
+	fn func(V)
+}
+
+type noArgListenerBinding[V View] struct {
+	name string
+}
+
+func newNoArgListener0[V View](fn func()) noArgListener[V] {
+	obj := new(noArgListener0[V])
+	obj.fn = fn
+	return obj
+}
+
+func (data *noArgListener0[V]) Run(_ V) {
+	data.fn()
+}
+
+func (data *noArgListener0[V]) rawListener() any {
+	return data.fn
+}
+
+func newNoArgListenerV[V View](fn func(V)) noArgListener[V] {
+	obj := new(noArgListenerV[V])
+	obj.fn = fn
+	return obj
+}
+
+func (data *noArgListenerV[V]) Run(view V) {
+	data.fn(view)
+}
+
+func (data *noArgListenerV[V]) rawListener() any {
+	return data.fn
+}
+
+func newNoArgListenerBinding[V View](name string) noArgListener[V] {
+	obj := new(noArgListenerBinding[V])
+	obj.name = name
+	return obj
+}
+
+func (data *noArgListenerBinding[V]) Run(view V) {
+	bind := view.binding()
+	if bind == nil {
+		ErrorLogF(`There is no a binding object for call "%s"`, data.name)
+		return
+	}
+
+	val := reflect.ValueOf(bind)
+	method := val.MethodByName(data.name)
+	if !method.IsValid() {
+		ErrorLogF(`The "%s" method is not valid`, data.name)
+		return
+	}
+
+	methodType := method.Type()
+	var args []reflect.Value = nil
+	switch methodType.NumIn() {
+	case 0:
+		args = []reflect.Value{}
+
+	case 1:
+		if equalType(methodType.In(0), reflect.TypeOf(view)) {
+			args = []reflect.Value{reflect.ValueOf(view)}
+		}
+	}
+
+	if args != nil {
+		method.Call(args)
+	} else {
+		ErrorLogF(`Unsupported prototype of "%s" method`, data.name)
+	}
+}
+
+func equalType(inType reflect.Type, argType reflect.Type) bool {
+	return inType == argType || (inType.Kind() == reflect.Interface && argType.Implements(inType))
+}
+
+func (data *noArgListenerBinding[V]) rawListener() any {
+	return data.name
+}
+
+func valueToNoArgEventListeners[V View](value any) ([]noArgListener[V], bool) {
+	if value == nil {
+		return nil, true
+	}
+
+	switch value := value.(type) {
+	case []noArgListener[V]:
+		return value, true
+
+	case noArgListener[V]:
+		return []noArgListener[V]{value}, true
+
+	case string:
+		return []noArgListener[V]{newNoArgListenerBinding[V](value)}, true
+
+	case func(V):
+		return []noArgListener[V]{newNoArgListenerV(value)}, true
+
+	case func():
+		return []noArgListener[V]{newNoArgListener0[V](value)}, true
+
+	case []func(V):
+		result := make([]noArgListener[V], 0, len(value))
+		for _, fn := range value {
+			if fn != nil {
+				result = append(result, newNoArgListenerV(fn))
+			}
+		}
+		return result, len(result) > 0
+
+	case []func():
+		result := make([]noArgListener[V], 0, len(value))
+		for _, fn := range value {
+			if fn != nil {
+				result = append(result, newNoArgListener0[V](fn))
+			}
+		}
+		return result, len(result) > 0
+
+	case []any:
+		result := make([]noArgListener[V], 0, len(value))
+		for _, v := range value {
+			if v != nil {
+				switch v := v.(type) {
+				case func(V):
+					result = append(result, newNoArgListenerV(v))
+
+				case func():
+					result = append(result, newNoArgListener0[V](v))
+
+				case string:
+					result = append(result, newNoArgListenerBinding[V](v))
+
+				default:
+					return nil, false
+				}
+			}
+		}
+		return result, len(result) > 0
+	}
+
+	return nil, false
+}
+
+func setNoArgEventListener[V View](view View, tag PropertyName, value any) []PropertyName {
+	if listeners, ok := valueToNoArgEventListeners[V](value); ok {
+		return setArrayPropertyValue(view, tag, listeners)
+	}
+	notCompatibleType(tag, value)
+	return nil
+}
+
+func getNoArgEventListeners[V View](view View, subviewID []string, tag PropertyName) []noArgListener[V] {
+	if view = getSubview(view, subviewID); view != nil {
+		if value := view.Get(tag); value != nil {
+			if result, ok := value.([]noArgListener[V]); ok {
+				return result
+			}
+		}
+	}
+	return []noArgListener[V]{}
+}
+
+func getNoArgEventRawListeners[V View](view View, subviewID []string, tag PropertyName) []any {
+	listeners := getNoArgEventListeners[V](view, subviewID, tag)
+	result := make([]any, len(listeners))
+	for i, l := range listeners {
+		result[i] = l.rawListener()
+	}
+	return result
+}
+
+func getNoArgBinding[V View](listeners []noArgListener[V]) string {
+	for _, listener := range listeners {
+		raw := listener.rawListener()
+		if text, ok := raw.(string); ok && text != "" {
+			return text
+		}
+	}
+	return ""
+}

events1arg.go

@@ -0,0 +1,271 @@
+package rui
+
+import (
+	"reflect"
+)
+
+type oneArgListener[V View, E any] interface {
+	Run(V, E)
+	rawListener() any
+}
+
+type oneArgListener0[V View, E any] struct {
+	fn func()
+}
+
+type oneArgListenerV[V View, E any] struct {
+	fn func(V)
+}
+
+type oneArgListenerE[V View, E any] struct {
+	fn func(E)
+}
+
+type oneArgListenerVE[V View, E any] struct {
+	fn func(V, E)
+}
+
+type oneArgListenerBinding[V View, E any] struct {
+	name string
+}
+
+func newOneArgListener0[V View, E any](fn func()) oneArgListener[V, E] {
+	obj := new(oneArgListener0[V, E])
+	obj.fn = fn
+	return obj
+}
+
+func (data *oneArgListener0[V, E]) Run(_ V, _ E) {
+	data.fn()
+}
+
+func (data *oneArgListener0[V, E]) rawListener() any {
+	return data.fn
+}
+
+func newOneArgListenerV[V View, E any](fn func(V)) oneArgListener[V, E] {
+	obj := new(oneArgListenerV[V, E])
+	obj.fn = fn
+	return obj
+}
+
+func (data *oneArgListenerV[V, E]) Run(view V, _ E) {
+	data.fn(view)
+}
+
+func (data *oneArgListenerV[V, E]) rawListener() any {
+	return data.fn
+}
+
+func newOneArgListenerE[V View, E any](fn func(E)) oneArgListener[V, E] {
+	obj := new(oneArgListenerE[V, E])
+	obj.fn = fn
+	return obj
+}
+
+func (data *oneArgListenerE[V, E]) Run(_ V, event E) {
+	data.fn(event)
+}
+
+func (data *oneArgListenerE[V, E]) rawListener() any {
+	return data.fn
+}
+
+func newOneArgListenerVE[V View, E any](fn func(V, E)) oneArgListener[V, E] {
+	obj := new(oneArgListenerVE[V, E])
+	obj.fn = fn
+	return obj
+}
+
+func (data *oneArgListenerVE[V, E]) Run(view V, arg E) {
+	data.fn(view, arg)
+}
+
+func (data *oneArgListenerVE[V, E]) rawListener() any {
+	return data.fn
+}
+
+func newOneArgListenerBinding[V View, E any](name string) oneArgListener[V, E] {
+	obj := new(oneArgListenerBinding[V, E])
+	obj.name = name
+	return obj
+}
+
+func (data *oneArgListenerBinding[V, E]) Run(view V, event E) {
+	bind := view.binding()
+	if bind == nil {
+		ErrorLogF(`There is no a binding object for call "%s"`, data.name)
+		return
+	}
+
+	val := reflect.ValueOf(bind)
+	method := val.MethodByName(data.name)
+	if !method.IsValid() {
+		ErrorLogF(`The "%s" method is not valid`, data.name)
+		return
+	}
+
+	methodType := method.Type()
+
+	var args []reflect.Value = nil
+	switch methodType.NumIn() {
+	case 0:
+		args = []reflect.Value{}
+
+	case 1:
+		inType := methodType.In(0)
+		if equalType(inType, reflect.TypeOf(event)) {
+			args = []reflect.Value{reflect.ValueOf(event)}
+		} else if equalType(inType, reflect.TypeOf(view)) {
+			args = []reflect.Value{reflect.ValueOf(view)}
+		}
+
+	case 2:
+		if equalType(methodType.In(0), reflect.TypeOf(view)) &&
+			equalType(methodType.In(1), reflect.TypeOf(event)) {
+			args = []reflect.Value{reflect.ValueOf(view), reflect.ValueOf(event)}
+		}
+	}
+
+	if args != nil {
+		method.Call(args)
+	} else {
+		ErrorLogF(`Unsupported prototype of "%s" method`, data.name)
+	}
+}
+
+func (data *oneArgListenerBinding[V, E]) rawListener() any {
+	return data.name
+}
+
+func valueToOneArgEventListeners[V View, E any](value any) ([]oneArgListener[V, E], bool) {
+	if value == nil {
+		return nil, true
+	}
+
+	switch value := value.(type) {
+	case []oneArgListener[V, E]:
+		return value, true
+
+	case oneArgListener[V, E]:
+		return []oneArgListener[V, E]{value}, true
+
+	case string:
+		return []oneArgListener[V, E]{newOneArgListenerBinding[V, E](value)}, true
+
+	case func(V, E):
+		return []oneArgListener[V, E]{newOneArgListenerVE(value)}, true
+
+	case func(V):
+		return []oneArgListener[V, E]{newOneArgListenerV[V, E](value)}, true
+
+	case func(E):
+		return []oneArgListener[V, E]{newOneArgListenerE[V](value)}, true
+
+	case func():
+		return []oneArgListener[V, E]{newOneArgListener0[V, E](value)}, true
+
+	case []func(V, E):
+		result := make([]oneArgListener[V, E], 0, len(value))
+		for _, fn := range value {
+			if fn != nil {
+				result = append(result, newOneArgListenerVE(fn))
+			}
+		}
+		return result, len(result) > 0
+
+	case []func(E):
+		result := make([]oneArgListener[V, E], 0, len(value))
+		for _, fn := range value {
+			if fn != nil {
+				result = append(result, newOneArgListenerE[V](fn))
+			}
+		}
+		return result, len(result) > 0
+
+	case []func(V):
+		result := make([]oneArgListener[V, E], 0, len(value))
+		for _, fn := range value {
+			if fn != nil {
+				result = append(result, newOneArgListenerV[V, E](fn))
+			}
+		}
+		return result, len(result) > 0
+
+	case []func():
+		result := make([]oneArgListener[V, E], 0, len(value))
+		for _, fn := range value {
+			if fn != nil {
+				result = append(result, newOneArgListener0[V, E](fn))
+			}
+		}
+		return result, len(result) > 0
+
+	case []any:
+		result := make([]oneArgListener[V, E], 0, len(value))
+		for _, v := range value {
+			if v != nil {
+				switch v := v.(type) {
+				case func(V, E):
+					result = append(result, newOneArgListenerVE(v))
+
+				case func(E):
+					result = append(result, newOneArgListenerE[V](v))
+
+				case func(V):
+					result = append(result, newOneArgListenerV[V, E](v))
+
+				case func():
+					result = append(result, newOneArgListener0[V, E](v))
+
+				case string:
+					result = append(result, newOneArgListenerBinding[V, E](v))
+
+				default:
+					return nil, false
+				}
+			}
+		}
+		return result, len(result) > 0
+	}
+
+	return nil, false
+}
+
+func setOneArgEventListener[V View, T any](view View, tag PropertyName, value any) []PropertyName {
+	if listeners, ok := valueToOneArgEventListeners[V, T](value); ok {
+		return setArrayPropertyValue(view, tag, listeners)
+	}
+	notCompatibleType(tag, value)
+	return nil
+}
+
+func getOneArgEventListeners[V View, E any](view View, subviewID []string, tag PropertyName) []oneArgListener[V, E] {
+	if view = getSubview(view, subviewID); view != nil {
+		if value := view.Get(tag); value != nil {
+			if result, ok := value.([]oneArgListener[V, E]); ok {
+				return result
+			}
+		}
+	}
+	return []oneArgListener[V, E]{}
+}
+
+func getOneArgEventRawListeners[V View, E any](view View, subviewID []string, tag PropertyName) []any {
+	listeners := getOneArgEventListeners[V, E](view, subviewID, tag)
+	result := make([]any, len(listeners))
+	for i, l := range listeners {
+		result[i] = l.rawListener()
+	}
+	return result
+}
+
+func getOneArgBinding[V View, E any](listeners []oneArgListener[V, E]) string {
+	for _, listener := range listeners {
+		raw := listener.rawListener()
+		if text, ok := raw.(string); ok && text != "" {
+			return text
+		}
+	}
+	return ""
+}

events2arg.go

@@ -0,0 +1,345 @@
+package rui
+
+import "reflect"
+
+type twoArgListener[V View, E any] interface {
+	Run(V, E, E)
+	rawListener() any
+}
+
+type twoArgListener0[V View, E any] struct {
+	fn func()
+}
+
+type twoArgListenerV[V View, E any] struct {
+	fn func(V)
+}
+
+type twoArgListenerE[V View, E any] struct {
+	fn func(E)
+}
+
+type twoArgListenerVE[V View, E any] struct {
+	fn func(V, E)
+}
+
+type twoArgListenerEE[V View, E any] struct {
+	fn func(E, E)
+}
+
+type twoArgListenerVEE[V View, E any] struct {
+	fn func(V, E, E)
+}
+
+type twoArgListenerBinding[V View, E any] struct {
+	name string
+}
+
+func newTwoArgListener0[V View, E any](fn func()) twoArgListener[V, E] {
+	obj := new(twoArgListener0[V, E])
+	obj.fn = fn
+	return obj
+}
+
+func (data *twoArgListener0[V, E]) Run(_ V, _ E, _ E) {
+	data.fn()
+}
+
+func (data *twoArgListener0[V, E]) rawListener() any {
+	return data.fn
+}
+
+func newTwoArgListenerV[V View, E any](fn func(V)) twoArgListener[V, E] {
+	obj := new(twoArgListenerV[V, E])
+	obj.fn = fn
+	return obj
+}
+
+func (data *twoArgListenerV[V, E]) Run(view V, _ E, _ E) {
+	data.fn(view)
+}
+
+func (data *twoArgListenerV[V, E]) rawListener() any {
+	return data.fn
+}
+
+func newTwoArgListenerE[V View, E any](fn func(E)) twoArgListener[V, E] {
+	obj := new(twoArgListenerE[V, E])
+	obj.fn = fn
+	return obj
+}
+
+func (data *twoArgListenerE[V, E]) Run(_ V, arg E, _ E) {
+	data.fn(arg)
+}
+
+func (data *twoArgListenerE[V, E]) rawListener() any {
+	return data.fn
+}
+
+func newTwoArgListenerVE[V View, E any](fn func(V, E)) twoArgListener[V, E] {
+	obj := new(twoArgListenerVE[V, E])
+	obj.fn = fn
+	return obj
+}
+
+func (data *twoArgListenerVE[V, E]) Run(view V, arg E, _ E) {
+	data.fn(view, arg)
+}
+
+func (data *twoArgListenerVE[V, E]) rawListener() any {
+	return data.fn
+}
+
+func newTwoArgListenerEE[V View, E any](fn func(E, E)) twoArgListener[V, E] {
+	obj := new(twoArgListenerEE[V, E])
+	obj.fn = fn
+	return obj
+}
+
+func (data *twoArgListenerEE[V, E]) Run(_ V, arg1 E, arg2 E) {
+	data.fn(arg1, arg2)
+}
+
+func (data *twoArgListenerEE[V, E]) rawListener() any {
+	return data.fn
+}
+
+func newTwoArgListenerVEE[V View, E any](fn func(V, E, E)) twoArgListener[V, E] {
+	obj := new(twoArgListenerVEE[V, E])
+	obj.fn = fn
+	return obj
+}
+
+func (data *twoArgListenerVEE[V, E]) Run(view V, arg1 E, arg2 E) {
+	data.fn(view, arg1, arg2)
+}
+
+func (data *twoArgListenerVEE[V, E]) rawListener() any {
+	return data.fn
+}
+
+func newTwoArgListenerBinding[V View, E any](name string) twoArgListener[V, E] {
+	obj := new(twoArgListenerBinding[V, E])
+	obj.name = name
+	return obj
+}
+
+func (data *twoArgListenerBinding[V, E]) Run(view V, arg1 E, arg2 E) {
+	bind := view.binding()
+	if bind == nil {
+		ErrorLogF(`There is no a binding object for call "%s"`, data.name)
+		return
+	}
+
+	val := reflect.ValueOf(bind)
+	method := val.MethodByName(data.name)
+	if !method.IsValid() {
+		ErrorLogF(`The "%s" method is not valid`, data.name)
+		return
+	}
+
+	methodType := method.Type()
+
+	var args []reflect.Value = nil
+	switch methodType.NumIn() {
+	case 0:
+		args = []reflect.Value{}
+
+	case 1:
+		inType := methodType.In(0)
+		if equalType(inType, reflect.TypeOf(arg1)) {
+			args = []reflect.Value{reflect.ValueOf(arg1)}
+		} else if equalType(inType, reflect.TypeOf(view)) {
+			args = []reflect.Value{reflect.ValueOf(view)}
+		}
+
+	case 2:
+		inType0 := methodType.In(0)
+		inType1 := methodType.In(1)
+		if equalType(inType0, reflect.TypeOf(view)) && equalType(inType1, reflect.TypeOf(arg1)) {
+			args = []reflect.Value{reflect.ValueOf(view), reflect.ValueOf(arg1)}
+		} else if equalType(inType0, reflect.TypeOf(arg1)) && equalType(inType1, reflect.TypeOf(arg2)) {
+			args = []reflect.Value{reflect.ValueOf(arg1), reflect.ValueOf(arg2)}
+		}
+
+	case 3:
+		if equalType(methodType.In(0), reflect.TypeOf(view)) &&
+			equalType(methodType.In(1), reflect.TypeOf(arg1)) &&
+			equalType(methodType.In(2), reflect.TypeOf(arg2)) {
+			args = []reflect.Value{reflect.ValueOf(view), reflect.ValueOf(arg1), reflect.ValueOf(arg2)}
+		}
+	}
+
+	if args != nil {
+		method.Call(args)
+	} else {
+		ErrorLogF(`Unsupported prototype of "%s" method`, data.name)
+	}
+}
+
+func (data *twoArgListenerBinding[V, E]) rawListener() any {
+	return data.name
+}
+
+func valueToTwoArgEventListeners[V View, E any](value any) ([]twoArgListener[V, E], bool) {
+	if value == nil {
+		return nil, true
+	}
+
+	switch value := value.(type) {
+	case []twoArgListener[V, E]:
+		return value, true
+
+	case twoArgListener[V, E]:
+		return []twoArgListener[V, E]{value}, true
+
+	case string:
+		return []twoArgListener[V, E]{newTwoArgListenerBinding[V, E](value)}, true
+
+	case func(V, E):
+		return []twoArgListener[V, E]{newTwoArgListenerVE(value)}, true
+
+	case func(V):
+		return []twoArgListener[V, E]{newTwoArgListenerV[V, E](value)}, true
+
+	case func(E):
+		return []twoArgListener[V, E]{newTwoArgListenerE[V](value)}, true
+
+	case func():
+		return []twoArgListener[V, E]{newTwoArgListener0[V, E](value)}, true
+
+	case func(E, E):
+		return []twoArgListener[V, E]{newTwoArgListenerEE[V](value)}, true
+
+	case func(V, E, E):
+		return []twoArgListener[V, E]{newTwoArgListenerVEE(value)}, true
+
+	case []func(V, E):
+		result := make([]twoArgListener[V, E], 0, len(value))
+		for _, fn := range value {
+			if fn != nil {
+				result = append(result, newTwoArgListenerVE(fn))
+			}
+		}
+		return result, len(result) > 0
+
+	case []func(E):
+		result := make([]twoArgListener[V, E], 0, len(value))
+		for _, fn := range value {
+			if fn != nil {
+				result = append(result, newTwoArgListenerE[V](fn))
+			}
+		}
+		return result, len(result) > 0
+
+	case []func(V):
+		result := make([]twoArgListener[V, E], 0, len(value))
+		for _, fn := range value {
+			if fn != nil {
+				result = append(result, newTwoArgListenerV[V, E](fn))
+			}
+		}
+		return result, len(result) > 0
+
+	case []func():
+		result := make([]twoArgListener[V, E], 0, len(value))
+		for _, fn := range value {
+			if fn != nil {
+				result = append(result, newTwoArgListener0[V, E](fn))
+			}
+		}
+		return result, len(result) > 0
+
+	case []func(E, E):
+		result := make([]twoArgListener[V, E], 0, len(value))
+		for _, fn := range value {
+			if fn != nil {
+				result = append(result, newTwoArgListenerEE[V](fn))
+			}
+		}
+		return result, len(result) > 0
+
+	case []func(V, E, E):
+		result := make([]twoArgListener[V, E], 0, len(value))
+		for _, fn := range value {
+			if fn != nil {
+				result = append(result, newTwoArgListenerVEE(fn))
+			}
+		}
+		return result, len(result) > 0
+
+	case []any:
+		result := make([]twoArgListener[V, E], 0, len(value))
+		for _, v := range value {
+			if v != nil {
+				switch v := v.(type) {
+				case func(V, E):
+					result = append(result, newTwoArgListenerVE(v))
+
+				case func(E):
+					result = append(result, newTwoArgListenerE[V](v))
+
+				case func(V):
+					result = append(result, newTwoArgListenerV[V, E](v))
+
+				case func():
+					result = append(result, newTwoArgListener0[V, E](v))
+
+				case func(E, E):
+					result = append(result, newTwoArgListenerEE[V](v))
+
+				case func(V, E, E):
+					result = append(result, newTwoArgListenerVEE(v))
+
+				case string:
+					result = append(result, newTwoArgListenerBinding[V, E](v))
+
+				default:
+					return nil, false
+				}
+			}
+		}
+		return result, len(result) > 0
+	}
+
+	return nil, false
+}
+
+func setTwoArgEventListener[V View, T any](view View, tag PropertyName, value any) []PropertyName {
+	if listeners, ok := valueToTwoArgEventListeners[V, T](value); ok {
+		return setArrayPropertyValue(view, tag, listeners)
+	}
+	notCompatibleType(tag, value)
+	return nil
+}
+
+func getTwoArgEventListeners[V View, E any](view View, subviewID []string, tag PropertyName) []twoArgListener[V, E] {
+	if view = getSubview(view, subviewID); view != nil {
+		if value := view.Get(tag); value != nil {
+			if result, ok := value.([]twoArgListener[V, E]); ok {
+				return result
+			}
+		}
+	}
+	return []twoArgListener[V, E]{}
+}
+
+func getTwoArgEventRawListeners[V View, E any](view View, subviewID []string, tag PropertyName) []any {
+	listeners := getTwoArgEventListeners[V, E](view, subviewID, tag)
+	result := make([]any, len(listeners))
+	for i, l := range listeners {
+		result[i] = l.rawListener()
+	}
+	return result
+}
+
+func getTwoArgBinding[V View, E any](listeners []twoArgListener[V, E]) string {
+	for _, listener := range listeners {
+		raw := listener.rawListener()
+		if text, ok := raw.(string); ok && text != "" {
+			return text
+		}
+	}
+	return ""
+}

filePicker.go

@@ -147,7 +147,7 @@ func (picker *filePickerData) Files() []FileInfo {
 func (picker *filePickerData) LoadFile(file FileInfo, result func(FileInfo, []byte)) {
 	if result != nil {
 		for i, info := range picker.files {
-			if info.Name == file.Name && info.Size == file.Size && info.LastModified == file.LastModified {
+			if info.Name == file.Name && info.Size == file.Size && info.LastModified.Equal(file.LastModified) {
 				if info.data != nil {
 					result(info, info.data)
 				} else {
@@ -282,8 +282,8 @@ func (picker *filePickerData) handleCommand(self View, command PropertyName, dat
 	case "fileSelected":
 		if files := parseFilesTag(data); files != nil {
 			picker.files = files
-			for _, listener := range GetFileSelectedListeners(picker) {
-				listener(picker, files)
+			for _, listener := range getOneArgEventListeners[FilePicker, []FileInfo](picker, nil, FileSelectedEvent) {
+				listener.Run(picker, files)
 			}
 		}
 		return true
@@ -317,13 +317,17 @@ func LoadFilePickerFile(view View, subviewID string, file FileInfo, result func(
 }
 
 // IsMultipleFilePicker returns "true" if multiple files can be selected in the FilePicker, "false" otherwise.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func IsMultipleFilePicker(view View, subviewID ...string) bool {
 	return boolStyledProperty(view, subviewID, Multiple, false)
 }
 
 // GetFilePickerAccept returns sets the list of allowed file extensions or MIME types.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetFilePickerAccept(view View, subviewID ...string) []string {
 	if view = getSubview(view, subviewID); view != nil {
 		accept, ok := stringProperty(view, Accept, view.Session())
@@ -345,7 +349,16 @@ func GetFilePickerAccept(view View, subviewID ...string) []string {
 
 // GetFileSelectedListeners returns the "file-selected-event" listener list.
 // If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetFileSelectedListeners(view View, subviewID ...string) []func(FilePicker, []FileInfo) {
-	return getOneArgEventListeners[FilePicker, []FileInfo](view, subviewID, FileSelectedEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.View, []rui.FileInfo),
+//   - func(rui.View),
+//   - func([]rui.FileInfo),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetFileSelectedListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[FilePicker, []FileInfo](view, subviewID, FileSelectedEvent)
 }

focusEvents.go

@@ -49,13 +49,27 @@ func focusEventsHtml(view View, buffer *strings.Builder) {
 }
 
 // GetFocusListeners returns a FocusListener list. If there are no listeners then the empty list is returned
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetFocusListeners(view View, subviewID ...string) []func(View) {
-	return getNoArgEventListeners[View](view, subviewID, FocusEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.View),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetFocusListeners(view View, subviewID ...string) []any {
+	return getNoArgEventRawListeners[View](view, subviewID, FocusEvent)
 }
 
 // GetLostFocusListeners returns a LostFocusListener list. If there are no listeners then the empty list is returned
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetLostFocusListeners(view View, subviewID ...string) []func(View) {
-	return getNoArgEventListeners[View](view, subviewID, LostFocusEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.View),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetLostFocusListeners(view View, subviewID ...string) []any {
+	return getNoArgEventRawListeners[View](view, subviewID, LostFocusEvent)
 }

gridLayout.go

@@ -458,10 +458,7 @@ func (gridLayout *gridLayoutData) UpdateGridContent() {
 		if gridLayout.created {
 			updateInnerHTML(gridLayout.htmlID(), gridLayout.session)
 		}
-
-		if listener, ok := gridLayout.changeListener[Content]; ok {
-			listener(gridLayout, Content)
-		}
+		gridLayout.contentChanged()
 	}
 }
 
@@ -506,26 +503,34 @@ func gridCellSizes(properties Properties, tag PropertyName, session Session) []S
 }
 
 // GetCellVerticalAlign returns the vertical align of a GridLayout cell content: TopAlign (0), BottomAlign (1), CenterAlign (2), StretchAlign (3)
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetCellVerticalAlign(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, CellVerticalAlign, StretchAlign, false)
 }
 
 // GetCellHorizontalAlign returns the vertical align of a GridLayout cell content: LeftAlign (0), RightAlign (1), CenterAlign (2), StretchAlign (3)
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetCellHorizontalAlign(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, CellHorizontalAlign, StretchAlign, false)
 }
 
 // GetGridAutoFlow returns the value of the  "grid-auto-flow" property
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetGridAutoFlow(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, GridAutoFlow, 0, false)
 }
 
 // GetCellWidth returns the width of a GridLayout cell. If the result is an empty array, then the width is not set.
 // If the result is a single value array, then the width of all cell is equal.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetCellWidth(view View, subviewID ...string) []SizeUnit {
 	if view = getSubview(view, subviewID); view != nil {
 		return gridCellSizes(view, CellWidth, view.Session())
@@ -535,7 +540,9 @@ func GetCellWidth(view View, subviewID ...string) []SizeUnit {
 
 // GetCellHeight returns the height of a GridLayout cell. If the result is an empty array, then the height is not set.
 // If the result is a single value array, then the height of all cell is equal.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetCellHeight(view View, subviewID ...string) []SizeUnit {
 	if view = getSubview(view, subviewID); view != nil {
 		return gridCellSizes(view, CellHeight, view.Session())
@@ -544,13 +551,17 @@ func GetCellHeight(view View, subviewID ...string) []SizeUnit {
 }
 
 // GetGridRowGap returns the gap between GridLayout rows.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetGridRowGap(view View, subviewID ...string) SizeUnit {
 	return sizeStyledProperty(view, subviewID, GridRowGap, false)
 }
 
 // GetGridColumnGap returns the gap between GridLayout columns.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetGridColumnGap(view View, subviewID ...string) SizeUnit {
 	return sizeStyledProperty(view, subviewID, GridColumnGap, false)
 }

image.go

@@ -4,34 +4,44 @@ import (
 	"strconv"
 )
 
+// ImageLoadingStatus defines type of status of the image loading
+type ImageLoadingStatus int
+
 // Constants which represent return values of the LoadingStatus function of an [Image] view
 const (
 	// ImageLoading is the image loading status: in the process of loading
-	ImageLoading = 0
+	ImageLoading ImageLoadingStatus = 0
 	// ImageReady is the image loading status: the image is loaded successfully
-	ImageReady = 1
+	ImageReady ImageLoadingStatus = 1
 	// ImageLoadingError is the image loading status: an error occurred while loading
-	ImageLoadingError = 2
+	ImageLoadingError ImageLoadingStatus = 2
 )
 
 // Image defines the image that is used for drawing operations on the Canvas.
 type Image interface {
 	// URL returns the url of the image
 	URL() string
-	// LoadingStatus returns the status of the image loading: ImageLoading (0), ImageReady (1), ImageLoadingError (2)
-	LoadingStatus() int
+
+	// LoadingStatus returns the status of the image loading:
+	//  - ImageLoading (0) - in the process of loading;
+	//  - ImageReady (1) - the image is loaded successfully;
+	//  - ImageLoadingError (2) - an error occurred while loading.
+	LoadingStatus() ImageLoadingStatus
+
 	// LoadingError: if LoadingStatus() == ImageLoadingError then returns the error text, "" otherwise
 	LoadingError() string
 	setLoadingError(err string)
+
 	// Width returns the width of the image in pixels. While LoadingStatus() != ImageReady returns 0
 	Width() float64
+
 	// Height returns the height of the image in pixels. While LoadingStatus() != ImageReady returns 0
 	Height() float64
 }
 
 type imageData struct {
 	url           string
-	loadingStatus int
+	loadingStatus ImageLoadingStatus
 	loadingError  string
 	width, height float64
 	listener      func(Image)
@@ -45,7 +55,7 @@ func (image *imageData) URL() string {
 	return image.url
 }
 
-func (image *imageData) LoadingStatus() int {
+func (image *imageData) LoadingStatus() ImageLoadingStatus {
 	return image.loadingStatus
 }
 

imageView.go

@@ -205,7 +205,7 @@ func imageViewSrcSet(view View, path string) string {
 				buffer.WriteString(", ")
 			}
 			buffer.WriteString(src.path)
-			buffer.WriteString(fmt.Sprintf(" %gx", src.scale))
+			fmt.Fprintf(buffer, " %gx", src.scale)
 		}
 		return buffer.String()
 	}
@@ -300,7 +300,7 @@ func (imageView *imageViewData) handleCommand(self View, command PropertyName, d
 	switch command {
 	case "imageViewError":
 		for _, listener := range getNoArgEventListeners[ImageView](imageView, nil, ErrorEvent) {
-			listener(imageView)
+			listener.Run(imageView)
 		}
 
 	case "imageViewLoaded":
@@ -309,7 +309,7 @@ func (imageView *imageViewData) handleCommand(self View, command PropertyName, d
 		imageView.currentSrc, _ = data.PropertyValue("current-src")
 
 		for _, listener := range getNoArgEventListeners[ImageView](imageView, nil, LoadedEvent) {
-			listener(imageView)
+			listener.Run(imageView)
 		}
 
 	default:
@@ -370,3 +370,31 @@ func GetImageViewVerticalAlign(view View, subviewID ...string) int {
 func GetImageViewHorizontalAlign(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, ImageHorizontalAlign, LeftAlign, false)
 }
+
+// GetImageViewErrorEventListeners returns the list of "error-event" event listeners.
+// If there are no listeners then the empty list is returned
+//
+// Result elements can be of the following types:
+//   - func(rui.ImageView)
+//   - func()
+//   - string
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetImageViewErrorEventListeners(view View, subviewID ...string) []any {
+	return getNoArgEventRawListeners[View](view, subviewID, ErrorEvent)
+}
+
+// GetImageViewLoadedEventListeners returns the list of "loaded-event" event listeners.
+// If there are no listeners then the empty list is returned
+//
+// Result elements can be of the following types:
+//   - func(rui.ImageView)
+//   - func()
+//   - string
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetImageViewLoadedEventListeners(view View, subviewID ...string) []any {
+	return getNoArgEventRawListeners[View](view, subviewID, LoadedEvent)
+}

keyEvents.go

@@ -434,15 +434,13 @@ func (event *KeyEvent) init(data DataObject) {
 }
 
 func keyEventsHtml(view View, buffer *strings.Builder) {
-	if len(getOneArgEventListeners[View, KeyEvent](view, nil, KeyDownEvent)) > 0 {
+	if len(getOneArgEventListeners[View, KeyEvent](view, nil, KeyDownEvent)) > 0 ||
+		(view.Focusable() && len(getOneArgEventListeners[View, MouseEvent](view, nil, ClickEvent)) > 0) {
+
 		buffer.WriteString(`onkeydown="keyDownEvent(this, event)" `)
-	} else if view.Focusable() {
-		if len(getOneArgEventListeners[View, MouseEvent](view, nil, ClickEvent)) > 0 {
-			buffer.WriteString(`onkeydown="keyDownEvent(this, event)" `)
-		}
 	}
 
-	if listeners := getOneArgEventListeners[View, KeyEvent](view, nil, KeyUpEvent); len(listeners) > 0 {
+	if len(getOneArgEventListeners[View, KeyEvent](view, nil, KeyUpEvent)) > 0 {
 		buffer.WriteString(`onkeyup="keyUpEvent(this, event)" `)
 	}
 }
@@ -454,7 +452,7 @@ func handleKeyEvents(view View, tag PropertyName, data DataObject) {
 
 	if len(listeners) > 0 {
 		for _, listener := range listeners {
-			listener(view, event)
+			listener.Run(view, event)
 		}
 		return
 	}
@@ -477,20 +475,38 @@ func handleKeyEvents(view View, tag PropertyName, data DataObject) {
 				ScreenY:   view.Frame().Top + view.Frame().Height/2,
 			}
 			for _, listener := range listeners {
-				listener(view, clickEvent)
+				listener.Run(view, clickEvent)
 			}
 		}
 	}
 }
 
 // GetKeyDownListeners returns the "key-down-event" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetKeyDownListeners(view View, subviewID ...string) []func(View, KeyEvent) {
-	return getOneArgEventListeners[View, KeyEvent](view, subviewID, KeyDownEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.View, rui.KeyEvent),
+//   - func(rui.View),
+//   - func(rui.KeyEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetKeyDownListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, KeyEvent](view, subviewID, KeyDownEvent)
 }
 
 // GetKeyUpListeners returns the "key-up-event" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetKeyUpListeners(view View, subviewID ...string) []func(View, KeyEvent) {
-	return getOneArgEventListeners[View, KeyEvent](view, subviewID, KeyUpEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.View, rui.KeyEvent),
+//   - func(rui.View),
+//   - func(rui.KeyEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetKeyUpListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, KeyEvent](view, subviewID, KeyUpEvent)
 }

listLayout.go

@@ -196,30 +196,33 @@ func (listLayout *listLayoutData) UpdateContent() {
 		if listLayout.created {
 			updateInnerHTML(listLayout.htmlID(), listLayout.session)
 		}
-
-		if listener, ok := listLayout.changeListener[Content]; ok {
-			listener(listLayout, Content)
-		}
+		listLayout.contentChanged()
 	}
 }
 
-// GetListVerticalAlign returns the vertical align of a ListLayout or ListView sibview:
+// GetListVerticalAlign returns the vertical align of a ListLayout or ListView subview:
 // TopAlign (0), BottomAlign (1), CenterAlign (2), or StretchAlign (3)
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetListVerticalAlign(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, VerticalAlign, TopAlign, false)
 }
 
 // GetListHorizontalAlign returns the vertical align of a ListLayout or ListView subview:
 // LeftAlign (0), RightAlign (1), CenterAlign (2), or StretchAlign (3)
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetListHorizontalAlign(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, HorizontalAlign, LeftAlign, false)
 }
 
 // GetListOrientation returns the orientation of a ListLayout or ListView subview:
 // TopDownOrientation (0), StartToEndOrientation (1), BottomUpOrientation (2), or EndToStartOrientation (3)
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetListOrientation(view View, subviewID ...string) int {
 	if view = getSubview(view, subviewID); view != nil {
 		if orientation, ok := valueToOrientation(view.Get(Orientation), view.Session()); ok {
@@ -238,19 +241,25 @@ func GetListOrientation(view View, subviewID ...string) int {
 
 // GetListWrap returns the wrap type of a ListLayout or ListView subview:
 // ListWrapOff (0), ListWrapOn (1), or ListWrapReverse (2)
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetListWrap(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, ListWrap, ListWrapOff, false)
 }
 
 // GetListRowGap returns the gap between ListLayout or ListView rows.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetListRowGap(view View, subviewID ...string) SizeUnit {
 	return sizeStyledProperty(view, subviewID, ListRowGap, false)
 }
 
 // GetListColumnGap returns the gap between ListLayout or ListView columns.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetListColumnGap(view View, subviewID ...string) SizeUnit {
 	return sizeStyledProperty(view, subviewID, ListColumnGap, false)
 }

listView.go

@@ -122,19 +122,13 @@ type ListView interface {
 	// ReloadListViewData updates ListView content
 	ReloadListViewData()
 
-	//getCheckedItems() []int
 	getItemFrames() []Frame
 }
 
 type listViewData struct {
 	viewData
-	//adapter ListAdapter
-	//clickedListeners  []func(ListView, int)
-	//selectedListeners []func(ListView, int)
-	//checkedListeners  []func(ListView, []int)
 	items     []View
 	itemFrame []Frame
-	//checkedItem       []int
 }
 
 // NewListView creates the new list view
@@ -279,7 +273,7 @@ func (listView *listViewData) propertyChanged(tag PropertyName) {
 		if listeners := getOneArgEventListeners[ListView, int](listView, nil, ListItemSelectedEvent); len(listeners) > 0 {
 			current := GetCurrent(listView)
 			for _, listener := range listeners {
-				listener(listView, current)
+				listener.Run(listView, current)
 			}
 		}
 
@@ -288,7 +282,7 @@ func (listView *listViewData) propertyChanged(tag PropertyName) {
 		if listeners := getOneArgEventListeners[ListView, []int](listView, nil, ListItemCheckedEvent); len(listeners) > 0 {
 			checked := GetListViewCheckedItems(listView)
 			for _, listener := range listeners {
-				listener(listView, checked)
+				listener.Run(listView, checked)
 			}
 		}
 
@@ -342,7 +336,7 @@ func (listView *listViewData) setItems(value any) []PropertyName {
 			items := make([]View, len(value))
 			for i, val := range value {
 				if val.IsObject() {
-					if view := CreateViewFromObject(session, val.Object()); view != nil {
+					if view := CreateViewFromObject(session, val.Object(), nil); view != nil {
 						items[i] = view
 					} else {
 						return nil
@@ -540,7 +534,7 @@ func (listView *listViewData) getDivs(checkbox, hCheckboxAlign, vCheckboxAlign i
 	return onDivBuilder.String(), offDivBuilder.String(), contentBuilder.String()
 }
 
-func (listView *listViewData) checkboxItemDiv(checkbox, hCheckboxAlign, vCheckboxAlign int) string {
+func (listView *listViewData) checkboxItemDiv(hCheckboxAlign, vCheckboxAlign int) string {
 	itemStyleBuilder := allocStringBuilder()
 	defer freeStringBuilder(itemStyleBuilder)
 
@@ -627,7 +621,7 @@ func (listView *listViewData) checkboxSubviews(adapter ListAdapter, buffer *stri
 	hCheckboxAlign := GetListViewCheckboxHorizontalAlign(listView)
 	vCheckboxAlign := GetListViewCheckboxVerticalAlign(listView)
 
-	itemDiv := listView.checkboxItemDiv(checkbox, hCheckboxAlign, vCheckboxAlign)
+	itemDiv := listView.checkboxItemDiv(hCheckboxAlign, vCheckboxAlign)
 	onDiv, offDiv, contentDiv := listView.getDivs(checkbox, hCheckboxAlign, vCheckboxAlign)
 
 	current := GetCurrent(listView)
@@ -734,7 +728,7 @@ func (listView *listViewData) updateCheckboxItem(index int, checked bool) {
 	buffer := allocStringBuilder()
 	defer freeStringBuilder(buffer)
 
-	buffer.WriteString(listView.checkboxItemDiv(checkbox, hCheckboxAlign, vCheckboxAlign))
+	buffer.WriteString(listView.checkboxItemDiv(hCheckboxAlign, vCheckboxAlign))
 	if checked {
 		buffer.WriteString(onDiv)
 	} else {
@@ -966,10 +960,10 @@ func (listView *listViewData) handleCommand(self View, command PropertyName, dat
 func (listView *listViewData) handleCurrent(number int) {
 	listView.properties[Current] = number
 	for _, listener := range getOneArgEventListeners[ListView, int](listView, nil, ListItemSelectedEvent) {
-		listener(listView, number)
+		listener.Run(listView, number)
 	}
 	if listener, ok := listView.changeListener[Current]; ok {
-		listener(listView, Current)
+		listener.Run(listView, Current)
 	}
 }
 
@@ -1028,16 +1022,16 @@ func (listView *listViewData) onItemClick(number int) {
 
 		setArrayPropertyValue(listView, Checked, checkedItem)
 		if listener, ok := listView.changeListener[Checked]; ok {
-			listener(listView, Checked)
+			listener.Run(listView, Checked)
 		}
 
 		for _, listener := range getOneArgEventListeners[ListView, []int](listView, nil, ListItemCheckedEvent) {
-			listener(listView, checkedItem)
+			listener.Run(listView, checkedItem)
 		}
 	}
 
 	for _, listener := range getOneArgEventListeners[ListView, int](listView, nil, ListItemClickedEvent) {
-		listener(listView, number)
+		listener.Run(listView, number)
 	}
 
 }
@@ -1054,58 +1048,97 @@ func (listView *listViewData) onItemResize(self View, index string, x, y, width,
 }
 
 // GetVerticalAlign return the vertical align of a list: TopAlign (0), BottomAlign (1), CenterAlign (2), StretchAlign (3)
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetVerticalAlign(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, VerticalAlign, TopAlign, false)
 }
 
 // GetHorizontalAlign return the vertical align of a list/checkbox: LeftAlign (0), RightAlign (1), CenterAlign (2), StretchAlign (3)
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetHorizontalAlign(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, HorizontalAlign, LeftAlign, false)
 }
 
 // GetListItemClickedListeners returns a ListItemClickedListener of the ListView.
 // If there are no listeners then the empty list is returned
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetListItemClickedListeners(view View, subviewID ...string) []func(ListView, int) {
-	return getOneArgEventListeners[ListView, int](view, subviewID, ListItemClickedEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.ListView, int),
+//   - func(rui.ListView),
+//   - func(int),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetListItemClickedListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[ListView, int](view, subviewID, ListItemClickedEvent)
 }
 
 // GetListItemSelectedListeners returns a ListItemSelectedListener of the ListView.
 // If there are no listeners then the empty list is returned
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetListItemSelectedListeners(view View, subviewID ...string) []func(ListView, int) {
-	return getOneArgEventListeners[ListView, int](view, subviewID, ListItemSelectedEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.ListView, int),
+//   - func(rui.ListView),
+//   - func(int),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetListItemSelectedListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[ListView, int](view, subviewID, ListItemSelectedEvent)
 }
 
 // GetListItemCheckedListeners returns a ListItemCheckedListener of the ListView.
 // If there are no listeners then the empty list is returned
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetListItemCheckedListeners(view View, subviewID ...string) []func(ListView, []int) {
-	return getOneArgEventListeners[ListView, []int](view, subviewID, ListItemCheckedEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.ListView, []int),
+//   - func(rui.ListView),
+//   - func([]int),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetListItemCheckedListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[ListView, []int](view, subviewID, ListItemCheckedEvent)
 }
 
 // GetListItemWidth returns the width of a ListView item.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetListItemWidth(view View, subviewID ...string) SizeUnit {
 	return sizeStyledProperty(view, subviewID, ItemWidth, false)
 }
 
 // GetListItemHeight returns the height of a ListView item.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetListItemHeight(view View, subviewID ...string) SizeUnit {
 	return sizeStyledProperty(view, subviewID, ItemHeight, false)
 }
 
 // GetListViewCheckbox returns the ListView checkbox type: NoneCheckbox (0), SingleCheckbox (1), or MultipleCheckbox (2).
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetListViewCheckbox(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, ItemCheckbox, 0, false)
 }
 
 // GetListViewCheckedItems returns the array of ListView checked items.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetListViewCheckedItems(view View, subviewID ...string) []int {
 	if view = getSubview(view, subviewID); view != nil {
 		if value := view.getRaw(Checked); value != nil {
@@ -1138,34 +1171,44 @@ func IsListViewCheckedItem(view View, subviewID string, index int) bool {
 
 // GetListViewCheckboxVerticalAlign returns the vertical align of the ListView checkbox:
 // TopAlign (0), BottomAlign (1), CenterAlign (2)
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetListViewCheckboxVerticalAlign(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, CheckboxVerticalAlign, TopAlign, false)
 }
 
 // GetListViewCheckboxHorizontalAlign returns the horizontal align of the ListView checkbox:
 // LeftAlign (0), RightAlign (1), CenterAlign (2)
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetListViewCheckboxHorizontalAlign(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, CheckboxHorizontalAlign, LeftAlign, false)
 }
 
 // GetListItemVerticalAlign returns the vertical align of the ListView item content:
 // TopAlign (0), BottomAlign (1), CenterAlign (2)
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetListItemVerticalAlign(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, ItemVerticalAlign, TopAlign, false)
 }
 
 // ItemHorizontalAlign returns the horizontal align of the ListView item content:
 // LeftAlign (0), RightAlign (1), CenterAlign (2), StretchAlign (3)
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetListItemHorizontalAlign(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, ItemHorizontalAlign, LeftAlign, false)
 }
 
 // GetListItemFrame - returns the location and size of the ListView item in pixels.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetListItemFrame(view View, subviewID string, index int) Frame {
 	if subviewID != "" {
 		view = ViewByID(view, subviewID)
@@ -1182,7 +1225,9 @@ func GetListItemFrame(view View, subviewID string, index int) Frame {
 }
 
 // GetListViewAdapter - returns the ListView adapter.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetListViewAdapter(view View, subviewID ...string) ListAdapter {
 	if view = getSubview(view, subviewID); view != nil {
 		if value := view.Get(Items); value != nil {

mediaPlayer.go

@@ -3,6 +3,7 @@ package rui
 import (
 	"fmt"
 	"math"
+	"reflect"
 	"strconv"
 	"strings"
 )
@@ -488,7 +489,7 @@ const (
 	//   - player - Interface of a player which generated this event,
 	//   - code - Error code. See below,
 	//   - message - Error message,
-
+	//
 	// Error codes:
 	//   - 0 (PlayerErrorUnknown) - Unknown error,
 	//   - 1 (PlayerErrorAborted) - Fetching the associated resource was interrupted by a user request,
@@ -610,7 +611,7 @@ func (player *mediaPlayerData) setFunc(tag PropertyName, value any) []PropertyNa
 		return setOneArgEventListener[MediaPlayer, float64](player, tag, value)
 
 	case PlayerErrorEvent:
-		if listeners, ok := valueToPlayerErrorListeners(value); ok {
+		if listeners, ok := valueToMediaPlayerErrorListeners(value); ok {
 			return setArrayPropertyValue(player, tag, listeners)
 		}
 		notCompatibleType(tag, value)
@@ -677,131 +678,132 @@ func setMediaPlayerSource(properties Properties, value any) []PropertyName {
 	return []PropertyName{Source}
 }
 
-func valueToPlayerErrorListeners(value any) ([]func(MediaPlayer, int, string), bool) {
-	if value == nil {
-		return nil, true
-	}
-
-	switch value := value.(type) {
-	case func(MediaPlayer, int, string):
-		return []func(MediaPlayer, int, string){value}, true
-
-	case func(int, string):
-		fn := func(_ MediaPlayer, code int, message string) {
-			value(code, message)
-		}
-		return []func(MediaPlayer, int, string){fn}, true
-
-	case func(MediaPlayer):
-		fn := func(player MediaPlayer, _ int, _ string) {
-			value(player)
-		}
-		return []func(MediaPlayer, int, string){fn}, true
-
-	case func():
-		fn := func(MediaPlayer, int, string) {
-			value()
-		}
-		return []func(MediaPlayer, int, string){fn}, true
-
-	case []func(MediaPlayer, int, string):
-		if len(value) == 0 {
+/*
+	func valueToPlayerErrorListeners(value any) ([]func(MediaPlayer, int, string), bool) {
+		if value == nil {
 			return nil, true
 		}
-		for _, fn := range value {
-			if fn == nil {
-				return nil, false
-			}
-		}
-		return value, true
 
-	case []func(int, string):
-		count := len(value)
-		if count == 0 {
-			return nil, true
-		}
-		listeners := make([]func(MediaPlayer, int, string), count)
-		for i, v := range value {
-			if v == nil {
-				return nil, false
-			}
-			listeners[i] = func(_ MediaPlayer, code int, message string) {
-				v(code, message)
-			}
-		}
-		return listeners, true
+		switch value := value.(type) {
+		case func(MediaPlayer, int, string):
+			return []func(MediaPlayer, int, string){value}, true
 
-	case []func(MediaPlayer):
-		count := len(value)
-		if count == 0 {
-			return nil, true
-		}
-		listeners := make([]func(MediaPlayer, int, string), count)
-		for i, v := range value {
-			if v == nil {
-				return nil, false
+		case func(int, string):
+			fn := func(_ MediaPlayer, code int, message string) {
+				value(code, message)
 			}
-			listeners[i] = func(player MediaPlayer, _ int, _ string) {
-				v(player)
-			}
-		}
-		return listeners, true
+			return []func(MediaPlayer, int, string){fn}, true
 
-	case []func():
-		count := len(value)
-		if count == 0 {
-			return nil, true
-		}
-		listeners := make([]func(MediaPlayer, int, string), count)
-		for i, v := range value {
-			if v == nil {
-				return nil, false
+		case func(MediaPlayer):
+			fn := func(player MediaPlayer, _ int, _ string) {
+				value(player)
 			}
-			listeners[i] = func(MediaPlayer, int, string) {
-				v()
-			}
-		}
-		return listeners, true
+			return []func(MediaPlayer, int, string){fn}, true
 
-	case []any:
-		count := len(value)
-		if count == 0 {
-			return nil, true
-		}
-		listeners := make([]func(MediaPlayer, int, string), count)
-		for i, v := range value {
-			if v == nil {
-				return nil, false
+		case func():
+			fn := func(MediaPlayer, int, string) {
+				value()
 			}
-			switch v := v.(type) {
-			case func(MediaPlayer, int, string):
-				listeners[i] = v
+			return []func(MediaPlayer, int, string){fn}, true
 
-			case func(int, string):
+		case []func(MediaPlayer, int, string):
+			if len(value) == 0 {
+				return nil, true
+			}
+			for _, fn := range value {
+				if fn == nil {
+					return nil, false
+				}
+			}
+			return value, true
+
+		case []func(int, string):
+			count := len(value)
+			if count == 0 {
+				return nil, true
+			}
+			listeners := make([]func(MediaPlayer, int, string), count)
+			for i, v := range value {
+				if v == nil {
+					return nil, false
+				}
 				listeners[i] = func(_ MediaPlayer, code int, message string) {
 					v(code, message)
 				}
+			}
+			return listeners, true
 
-			case func(MediaPlayer):
+		case []func(MediaPlayer):
+			count := len(value)
+			if count == 0 {
+				return nil, true
+			}
+			listeners := make([]func(MediaPlayer, int, string), count)
+			for i, v := range value {
+				if v == nil {
+					return nil, false
+				}
 				listeners[i] = func(player MediaPlayer, _ int, _ string) {
 					v(player)
 				}
+			}
+			return listeners, true
 
-			case func():
+		case []func():
+			count := len(value)
+			if count == 0 {
+				return nil, true
+			}
+			listeners := make([]func(MediaPlayer, int, string), count)
+			for i, v := range value {
+				if v == nil {
+					return nil, false
+				}
 				listeners[i] = func(MediaPlayer, int, string) {
 					v()
 				}
-
-			default:
-				return nil, false
 			}
+			return listeners, true
+
+		case []any:
+			count := len(value)
+			if count == 0 {
+				return nil, true
+			}
+			listeners := make([]func(MediaPlayer, int, string), count)
+			for i, v := range value {
+				if v == nil {
+					return nil, false
+				}
+				switch v := v.(type) {
+				case func(MediaPlayer, int, string):
+					listeners[i] = v
+
+				case func(int, string):
+					listeners[i] = func(_ MediaPlayer, code int, message string) {
+						v(code, message)
+					}
+
+				case func(MediaPlayer):
+					listeners[i] = func(player MediaPlayer, _ int, _ string) {
+						v(player)
+					}
+
+				case func():
+					listeners[i] = func(MediaPlayer, int, string) {
+						v()
+					}
+
+				default:
+					return nil, false
+				}
+			}
+			return listeners, true
 		}
-		return listeners, true
+
+		return nil, false
 	}
-
-	return nil, false
-}
-
+*/
 func mediaPlayerEvents() map[PropertyName]string {
 	return map[PropertyName]string{
 		AbortEvent:          "onabort",
@@ -981,31 +983,23 @@ func (player *mediaPlayerData) handleCommand(self View, command PropertyName, da
 		PlayingEvent, ProgressEvent, SeekedEvent, SeekingEvent, StalledEvent, SuspendEvent,
 		WaitingEvent:
 
-		if value := player.getRaw(command); value != nil {
-			if listeners, ok := value.([]func(MediaPlayer)); ok {
-				for _, listener := range listeners {
-					listener(player)
-				}
-			}
+		for _, listener := range getNoArgEventListeners[MediaPlayer](player, nil, command) {
+			listener.Run(player)
 		}
 
 	case TimeUpdateEvent, DurationChangedEvent, RateChangedEvent, VolumeChangedEvent:
-		if value := player.getRaw(command); value != nil {
-			if listeners, ok := value.([]func(MediaPlayer, float64)); ok {
-				time := dataFloatProperty(data, "value")
-				for _, listener := range listeners {
-					listener(player, time)
-				}
-			}
+		time := dataFloatProperty(data, "value")
+		for _, listener := range getOneArgEventListeners[MediaPlayer, float64](player, nil, command) {
+			listener.Run(player, time)
 		}
 
 	case PlayerErrorEvent:
 		if value := player.getRaw(command); value != nil {
-			if listeners, ok := value.([]func(MediaPlayer, int, string)); ok {
+			if listeners, ok := value.([]mediaPlayerErrorListener); ok {
 				code, _ := dataIntProperty(data, "code")
 				message, _ := data.PropertyValue("message")
 				for _, listener := range listeners {
-					listener(player, code, message)
+					listener.Run(player, code, message)
 				}
 			}
 		}
@@ -1254,3 +1248,393 @@ func IsMediaPlayerPaused(view View, playerID string) bool {
 	ErrorLog(`The found View is not MediaPlayer`)
 	return false
 }
+
+type mediaPlayerErrorListener interface {
+	Run(MediaPlayer, int, string)
+	rawListener() any
+}
+
+type mediaPlayerErrorListener0 struct {
+	fn func()
+}
+
+type mediaPlayerErrorListenerP struct {
+	fn func(MediaPlayer)
+}
+
+type mediaPlayerErrorListenerI struct {
+	fn func(int)
+}
+
+type mediaPlayerErrorListenerS struct {
+	fn func(string)
+}
+
+type mediaPlayerErrorListenerPI struct {
+	fn func(MediaPlayer, int)
+}
+
+type mediaPlayerErrorListenerPS struct {
+	fn func(MediaPlayer, string)
+}
+
+type mediaPlayerErrorListenerIS struct {
+	fn func(int, string)
+}
+
+type mediaPlayerErrorListenerPIS struct {
+	fn func(MediaPlayer, int, string)
+}
+
+type mediaPlayerErrorListenerBinding struct {
+	name string
+}
+
+func newMediaPlayerErrorListener0(fn func()) mediaPlayerErrorListener {
+	obj := new(mediaPlayerErrorListener0)
+	obj.fn = fn
+	return obj
+}
+
+func (data *mediaPlayerErrorListener0) Run(_ MediaPlayer, _ int, _ string) {
+	data.fn()
+}
+
+func (data *mediaPlayerErrorListener0) rawListener() any {
+	return data.fn
+}
+
+func newMediaPlayerErrorListenerP(fn func(MediaPlayer)) mediaPlayerErrorListener {
+	obj := new(mediaPlayerErrorListenerP)
+	obj.fn = fn
+	return obj
+}
+
+func (data *mediaPlayerErrorListenerP) Run(player MediaPlayer, _ int, _ string) {
+	data.fn(player)
+}
+
+func (data *mediaPlayerErrorListenerP) rawListener() any {
+	return data.fn
+}
+
+func newMediaPlayerErrorListenerI(fn func(int)) mediaPlayerErrorListener {
+	obj := new(mediaPlayerErrorListenerI)
+	obj.fn = fn
+	return obj
+}
+
+func (data *mediaPlayerErrorListenerI) Run(_ MediaPlayer, code int, _ string) {
+	data.fn(code)
+}
+
+func (data *mediaPlayerErrorListenerI) rawListener() any {
+	return data.fn
+}
+
+func newMediaPlayerErrorListenerS(fn func(string)) mediaPlayerErrorListener {
+	obj := new(mediaPlayerErrorListenerS)
+	obj.fn = fn
+	return obj
+}
+
+func (data *mediaPlayerErrorListenerS) Run(_ MediaPlayer, _ int, message string) {
+	data.fn(message)
+}
+
+func (data *mediaPlayerErrorListenerS) rawListener() any {
+	return data.fn
+}
+
+func newMediaPlayerErrorListenerPI(fn func(MediaPlayer, int)) mediaPlayerErrorListener {
+	obj := new(mediaPlayerErrorListenerPI)
+	obj.fn = fn
+	return obj
+}
+
+func (data *mediaPlayerErrorListenerPI) Run(player MediaPlayer, code int, _ string) {
+	data.fn(player, code)
+}
+
+func (data *mediaPlayerErrorListenerPI) rawListener() any {
+	return data.fn
+}
+
+func newMediaPlayerErrorListenerPS(fn func(MediaPlayer, string)) mediaPlayerErrorListener {
+	obj := new(mediaPlayerErrorListenerPS)
+	obj.fn = fn
+	return obj
+}
+
+func (data *mediaPlayerErrorListenerPS) Run(player MediaPlayer, _ int, message string) {
+	data.fn(player, message)
+}
+
+func (data *mediaPlayerErrorListenerPS) rawListener() any {
+	return data.fn
+}
+
+func newMediaPlayerErrorListenerIS(fn func(int, string)) mediaPlayerErrorListener {
+	obj := new(mediaPlayerErrorListenerIS)
+	obj.fn = fn
+	return obj
+}
+
+func (data *mediaPlayerErrorListenerIS) Run(_ MediaPlayer, code int, message string) {
+	data.fn(code, message)
+}
+
+func (data *mediaPlayerErrorListenerIS) rawListener() any {
+	return data.fn
+}
+
+func newMediaPlayerErrorListenerPIS(fn func(MediaPlayer, int, string)) mediaPlayerErrorListener {
+	obj := new(mediaPlayerErrorListenerPIS)
+	obj.fn = fn
+	return obj
+}
+
+func (data *mediaPlayerErrorListenerPIS) Run(player MediaPlayer, code int, message string) {
+	data.fn(player, code, message)
+}
+
+func (data *mediaPlayerErrorListenerPIS) rawListener() any {
+	return data.fn
+}
+
+func newMediaPlayerErrorListenerBinding(name string) mediaPlayerErrorListener {
+	obj := new(mediaPlayerErrorListenerBinding)
+	obj.name = name
+	return obj
+}
+
+func (data *mediaPlayerErrorListenerBinding) Run(player MediaPlayer, code int, message string) {
+	bind := player.binding()
+	if bind == nil {
+		ErrorLogF(`There is no a binding object for call "%s"`, data.name)
+		return
+	}
+
+	val := reflect.ValueOf(bind)
+	method := val.MethodByName(data.name)
+	if !method.IsValid() {
+		ErrorLogF(`The "%s" method is not valid`, data.name)
+		return
+	}
+
+	methodType := method.Type()
+	var args []reflect.Value = nil
+
+	switch methodType.NumIn() {
+	case 0:
+		args = []reflect.Value{}
+
+	case 1:
+		inType := methodType.In(0)
+		if equalType(inType, reflect.TypeOf(player)) {
+			args = []reflect.Value{reflect.ValueOf(player)}
+		} else if equalType(inType, reflect.TypeOf(code)) {
+			args = []reflect.Value{reflect.ValueOf(code)}
+		} else if equalType(inType, reflect.TypeOf(message)) {
+			args = []reflect.Value{reflect.ValueOf(message)}
+		}
+
+	case 2:
+		in0 := methodType.In(0)
+		in1 := methodType.In(1)
+		if equalType(in0, reflect.TypeOf(player)) {
+			if equalType(in1, reflect.TypeOf(code)) {
+				args = []reflect.Value{reflect.ValueOf(player), reflect.ValueOf(code)}
+			} else if equalType(in1, reflect.TypeOf(message)) {
+				args = []reflect.Value{reflect.ValueOf(player), reflect.ValueOf(message)}
+			}
+		} else if equalType(in0, reflect.TypeOf(code)) && equalType(in1, reflect.TypeOf(message)) {
+			args = []reflect.Value{reflect.ValueOf(code), reflect.ValueOf(message)}
+		}
+
+	case 3:
+		if equalType(methodType.In(0), reflect.TypeOf(player)) &&
+			equalType(methodType.In(1), reflect.TypeOf(code)) &&
+			equalType(methodType.In(2), reflect.TypeOf(message)) {
+			args = []reflect.Value{
+				reflect.ValueOf(player),
+				reflect.ValueOf(code),
+				reflect.ValueOf(message),
+			}
+		}
+	}
+
+	if args != nil {
+		method.Call(args)
+	} else {
+		ErrorLogF(`Unsupported prototype of "%s" method`, data.name)
+	}
+}
+
+func (data *mediaPlayerErrorListenerBinding) rawListener() any {
+	return data.name
+}
+
+func valueToMediaPlayerErrorListeners(value any) ([]mediaPlayerErrorListener, bool) {
+	if value == nil {
+		return nil, true
+	}
+
+	switch value := value.(type) {
+	case []mediaPlayerErrorListener:
+		return value, true
+
+	case mediaPlayerErrorListener:
+		return []mediaPlayerErrorListener{value}, true
+
+	case string:
+		return []mediaPlayerErrorListener{newMediaPlayerErrorListenerBinding(value)}, true
+
+	case func():
+		return []mediaPlayerErrorListener{newMediaPlayerErrorListener0(value)}, true
+
+	case func(MediaPlayer):
+		return []mediaPlayerErrorListener{newMediaPlayerErrorListenerP(value)}, true
+
+	case func(int):
+		return []mediaPlayerErrorListener{newMediaPlayerErrorListenerI(value)}, true
+
+	case func(string):
+		return []mediaPlayerErrorListener{newMediaPlayerErrorListenerS(value)}, true
+
+	case func(MediaPlayer, int):
+		return []mediaPlayerErrorListener{newMediaPlayerErrorListenerPI(value)}, true
+
+	case func(MediaPlayer, string):
+		return []mediaPlayerErrorListener{newMediaPlayerErrorListenerPS(value)}, true
+
+	case func(int, string):
+		return []mediaPlayerErrorListener{newMediaPlayerErrorListenerIS(value)}, true
+
+	case func(MediaPlayer, int, string):
+		return []mediaPlayerErrorListener{newMediaPlayerErrorListenerPIS(value)}, true
+
+	case []func():
+		result := make([]mediaPlayerErrorListener, 0, len(value))
+		for _, fn := range value {
+			if fn != nil {
+				result = append(result, newMediaPlayerErrorListener0(fn))
+			}
+		}
+		return result, len(result) > 0
+
+	case []func(MediaPlayer):
+		result := make([]mediaPlayerErrorListener, 0, len(value))
+		for _, fn := range value {
+			if fn != nil {
+				result = append(result, newMediaPlayerErrorListenerP(fn))
+			}
+		}
+		return result, len(result) > 0
+
+	case []func(int):
+		result := make([]mediaPlayerErrorListener, 0, len(value))
+		for _, fn := range value {
+			if fn != nil {
+				result = append(result, newMediaPlayerErrorListenerI(fn))
+			}
+		}
+		return result, len(result) > 0
+
+	case []func(string):
+		result := make([]mediaPlayerErrorListener, 0, len(value))
+		for _, fn := range value {
+			if fn != nil {
+				result = append(result, newMediaPlayerErrorListenerS(fn))
+			}
+		}
+		return result, len(result) > 0
+
+	case []func(MediaPlayer, int):
+		result := make([]mediaPlayerErrorListener, 0, len(value))
+		for _, fn := range value {
+			if fn != nil {
+				result = append(result, newMediaPlayerErrorListenerPI(fn))
+			}
+		}
+		return result, len(result) > 0
+
+	case []func(MediaPlayer, string):
+		result := make([]mediaPlayerErrorListener, 0, len(value))
+		for _, fn := range value {
+			if fn != nil {
+				result = append(result, newMediaPlayerErrorListenerPS(fn))
+			}
+		}
+		return result, len(result) > 0
+
+	case []func(int, string):
+		result := make([]mediaPlayerErrorListener, 0, len(value))
+		for _, fn := range value {
+			if fn != nil {
+				result = append(result, newMediaPlayerErrorListenerIS(fn))
+			}
+		}
+		return result, len(result) > 0
+
+	case []func(MediaPlayer, int, string):
+		result := make([]mediaPlayerErrorListener, 0, len(value))
+		for _, fn := range value {
+			if fn != nil {
+				result = append(result, newMediaPlayerErrorListenerPIS(fn))
+			}
+		}
+		return result, len(result) > 0
+
+	case []any:
+		result := make([]mediaPlayerErrorListener, 0, len(value))
+		for _, v := range value {
+			if v != nil {
+				switch v := v.(type) {
+				case func():
+					result = append(result, newMediaPlayerErrorListener0(v))
+
+				case func(MediaPlayer):
+					result = append(result, newMediaPlayerErrorListenerP(v))
+
+				case func(int):
+					result = append(result, newMediaPlayerErrorListenerI(v))
+
+				case func(string):
+					result = append(result, newMediaPlayerErrorListenerS(v))
+
+				case func(MediaPlayer, int):
+					result = append(result, newMediaPlayerErrorListenerPI(v))
+
+				case func(MediaPlayer, string):
+					result = append(result, newMediaPlayerErrorListenerPS(v))
+
+				case func(int, string):
+					result = append(result, newMediaPlayerErrorListenerIS(v))
+
+				case func(MediaPlayer, int, string):
+					result = append(result, newMediaPlayerErrorListenerPIS(v))
+
+				case string:
+					result = append(result, newMediaPlayerErrorListenerBinding(v))
+
+				default:
+					return nil, false
+				}
+			}
+		}
+		return result, len(result) > 0
+	}
+
+	return nil, false
+}
+
+func getMediaPlayerErrorListenerBinding(listeners []mediaPlayerErrorListener) string {
+	for _, listener := range listeners {
+		raw := listener.rawListener()
+		if text, ok := raw.(string); ok && text != "" {
+			return text
+		}
+	}
+	return ""
+}

mouseEvents.go

@@ -280,56 +280,128 @@ func handleMouseEvents(view View, tag PropertyName, data DataObject) {
 		event.init(data)
 
 		for _, listener := range listeners {
-			listener(view, event)
+			listener.Run(view, event)
 		}
 	}
 }
 
 // GetClickListeners returns the "click-event" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetClickListeners(view View, subviewID ...string) []func(View, MouseEvent) {
-	return getOneArgEventListeners[View, MouseEvent](view, subviewID, ClickEvent)
+//
+// Result elements can be of the following types:
+//   - func(View, MouseEvent),
+//   - func(View),
+//   - func(MouseEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetClickListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, MouseEvent](view, subviewID, ClickEvent)
 }
 
 // GetDoubleClickListeners returns the "double-click-event" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetDoubleClickListeners(view View, subviewID ...string) []func(View, MouseEvent) {
-	return getOneArgEventListeners[View, MouseEvent](view, subviewID, DoubleClickEvent)
+//
+// Result elements can be of the following types:
+//   - func(View, MouseEvent),
+//   - func(View),
+//   - func(MouseEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetDoubleClickListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, MouseEvent](view, subviewID, DoubleClickEvent)
 }
 
 // GetContextMenuListeners returns the "context-menu" listener list.
 // If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetContextMenuListeners(view View, subviewID ...string) []func(View, MouseEvent) {
-	return getOneArgEventListeners[View, MouseEvent](view, subviewID, ContextMenuEvent)
+//
+// Result elements can be of the following types:
+//   - func(View, MouseEvent),
+//   - func(View),
+//   - func(MouseEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetContextMenuListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, MouseEvent](view, subviewID, ContextMenuEvent)
 }
 
 // GetMouseDownListeners returns the "mouse-down" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetMouseDownListeners(view View, subviewID ...string) []func(View, MouseEvent) {
-	return getOneArgEventListeners[View, MouseEvent](view, subviewID, MouseDown)
+//
+// Result elements can be of the following types:
+//   - func(View, MouseEvent),
+//   - func(View),
+//   - func(MouseEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetMouseDownListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, MouseEvent](view, subviewID, MouseDown)
 }
 
 // GetMouseUpListeners returns the "mouse-up" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetMouseUpListeners(view View, subviewID ...string) []func(View, MouseEvent) {
-	return getOneArgEventListeners[View, MouseEvent](view, subviewID, MouseUp)
+//
+// Result elements can be of the following types:
+//   - func(View, MouseEvent),
+//   - func(View),
+//   - func(MouseEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetMouseUpListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, MouseEvent](view, subviewID, MouseUp)
 }
 
 // GetMouseMoveListeners returns the "mouse-move" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetMouseMoveListeners(view View, subviewID ...string) []func(View, MouseEvent) {
-	return getOneArgEventListeners[View, MouseEvent](view, subviewID, MouseMove)
+//
+// Result elements can be of the following types:
+//   - func(View, MouseEvent),
+//   - func(View),
+//   - func(MouseEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetMouseMoveListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, MouseEvent](view, subviewID, MouseMove)
 }
 
 // GetMouseOverListeners returns the "mouse-over" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetMouseOverListeners(view View, subviewID ...string) []func(View, MouseEvent) {
-	return getOneArgEventListeners[View, MouseEvent](view, subviewID, MouseOver)
+//
+// Result elements can be of the following types:
+//   - func(View, MouseEvent),
+//   - func(View),
+//   - func(MouseEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetMouseOverListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, MouseEvent](view, subviewID, MouseOver)
 }
 
 // GetMouseOutListeners returns the "mouse-out" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetMouseOutListeners(view View, subviewID ...string) []func(View, MouseEvent) {
-	return getOneArgEventListeners[View, MouseEvent](view, subviewID, MouseOut)
+//
+// Result elements can be of the following types:
+//   - func(View, MouseEvent),
+//   - func(View),
+//   - func(MouseEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetMouseOutListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, MouseEvent](view, subviewID, MouseOut)
 }

numberPicker.go

@@ -166,8 +166,8 @@ func (picker *numberPickerData) setFunc(tag PropertyName, value any) []PropertyN
 }
 
 func (picker *numberPickerData) numberFormat() string {
-	if precission := GetNumberPickerPrecision(picker); precission > 0 {
-		return fmt.Sprintf("%%.%df", precission)
+	if precision := GetNumberPickerPrecision(picker); precision > 0 {
+		return fmt.Sprintf("%%.%df", precision)
 	}
 	return "%g"
 }
@@ -201,7 +201,7 @@ func (picker *numberPickerData) propertyChanged(tag PropertyName) {
 		format := picker.numberFormat()
 		picker.Session().callFunc("setInputValue", picker.htmlID(), fmt.Sprintf(format, value))
 
-		if listeners := GetNumberChangedListeners(picker); len(listeners) > 0 {
+		if listeners := getTwoArgEventListeners[NumberPicker, float64](picker, nil, NumberChangedEvent); len(listeners) > 0 {
 			old := 0.0
 			if val := picker.getRaw("old-number"); val != nil {
 				if n, ok := val.(float64); ok {
@@ -210,7 +210,7 @@ func (picker *numberPickerData) propertyChanged(tag PropertyName) {
 			}
 			if old != value {
 				for _, listener := range listeners {
-					listener(picker, value, old)
+					listener.Run(picker, value, old)
 				}
 			}
 		}
@@ -244,27 +244,27 @@ func (picker *numberPickerData) htmlProperties(self View, buffer *strings.Builde
 	min, max := GetNumberPickerMinMax(picker)
 	if min != math.Inf(-1) {
 		buffer.WriteString(` min="`)
-		buffer.WriteString(fmt.Sprintf(format, min))
+		fmt.Fprintf(buffer, format, min)
 		buffer.WriteByte('"')
 	}
 
 	if max != math.Inf(1) {
 		buffer.WriteString(` max="`)
-		buffer.WriteString(fmt.Sprintf(format, max))
+		fmt.Fprintf(buffer, format, max)
 		buffer.WriteByte('"')
 	}
 
 	step := GetNumberPickerStep(picker)
 	if step != 0 {
 		buffer.WriteString(` step="`)
-		buffer.WriteString(fmt.Sprintf(format, step))
+		fmt.Fprintf(buffer, format, step)
 		buffer.WriteByte('"')
 	} else {
 		buffer.WriteString(` step="any"`)
 	}
 
 	buffer.WriteString(` value="`)
-	buffer.WriteString(fmt.Sprintf(format, GetNumberPickerValue(picker)))
+	fmt.Fprintf(buffer, format, GetNumberPickerValue(picker))
 	buffer.WriteByte('"')
 
 	buffer.WriteString(` oninput="editViewInputEvent(this)"`)
@@ -280,11 +280,11 @@ func (picker *numberPickerData) handleCommand(self View, command PropertyName, d
 				oldValue := GetNumberPickerValue(picker)
 				picker.properties[NumberPickerValue] = text
 				if value != oldValue {
-					for _, listener := range GetNumberChangedListeners(picker) {
-						listener(picker, value, oldValue)
+					for _, listener := range getTwoArgEventListeners[NumberPicker, float64](picker, nil, NumberChangedEvent) {
+						listener.Run(picker, value, oldValue)
 					}
 					if listener, ok := picker.changeListener[NumberPickerValue]; ok {
-						listener(picker, NumberPickerValue)
+						listener.Run(picker, NumberPickerValue)
 					}
 				}
 			}
@@ -298,13 +298,17 @@ func (picker *numberPickerData) handleCommand(self View, command PropertyName, d
 // GetNumberPickerType returns the type of NumberPicker subview. Valid values:
 // NumberEditor (0) - NumberPicker is presented by editor (default type);
 // NumberSlider (1) - NumberPicker is presented by slider.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetNumberPickerType(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, NumberPickerType, NumberEditor, false)
 }
 
 // GetNumberPickerMinMax returns the min and max value of NumberPicker subview.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetNumberPickerMinMax(view View, subviewID ...string) (float64, float64) {
 	view = getSubview(view, subviewID)
 	pickerType := GetNumberPickerType(view)
@@ -328,7 +332,9 @@ func GetNumberPickerMinMax(view View, subviewID ...string) (float64, float64) {
 }
 
 // GetNumberPickerStep returns the value changing step of NumberPicker subview.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetNumberPickerStep(view View, subviewID ...string) float64 {
 	view = getSubview(view, subviewID)
 	_, max := GetNumberPickerMinMax(view)
@@ -341,7 +347,9 @@ func GetNumberPickerStep(view View, subviewID ...string) float64 {
 }
 
 // GetNumberPickerValue returns the value of NumberPicker subview.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetNumberPickerValue(view View, subviewID ...string) float64 {
 	view = getSubview(view, subviewID)
 	min, _ := GetNumberPickerMinMax(view)
@@ -350,13 +358,26 @@ func GetNumberPickerValue(view View, subviewID ...string) float64 {
 
 // GetNumberChangedListeners returns the NumberChangedListener list of an NumberPicker subview.
 // If there are no listeners then the empty list is returned
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetNumberChangedListeners(view View, subviewID ...string) []func(NumberPicker, float64, float64) {
-	return getTwoArgEventListeners[NumberPicker, float64](view, subviewID, NumberChangedEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.NumberPicker, float64, float64),
+//   - func(rui.NumberPicker, float64),
+//   - func(rui.NumberPicker),
+//   - func(float64, float64),
+//   - func(float64),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetNumberChangedListeners(view View, subviewID ...string) []any {
+	return getTwoArgEventRawListeners[NumberPicker, float64](view, subviewID, NumberChangedEvent)
 }
 
 // GetNumberPickerPrecision returns the precision of displaying fractional part in editor of NumberPicker subview.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetNumberPickerPrecision(view View, subviewID ...string) int {
 	return intStyledProperty(view, subviewID, NumberPickerPrecision, 0)
 }

pointerEvents.go

@@ -192,42 +192,96 @@ func handlePointerEvents(view View, tag PropertyName, data DataObject) {
 	event.init(data)
 
 	for _, listener := range listeners {
-		listener(view, event)
+		listener.Run(view, event)
 	}
 }
 
 // GetPointerDownListeners returns the "pointer-down" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetPointerDownListeners(view View, subviewID ...string) []func(View, PointerEvent) {
-	return getOneArgEventListeners[View, PointerEvent](view, subviewID, PointerDown)
+//
+// Result elements can be of the following types:
+//   - func(View, PointerEvent),
+//   - func(View),
+//   - func(PointerEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetPointerDownListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, PointerEvent](view, subviewID, PointerDown)
 }
 
 // GetPointerUpListeners returns the "pointer-up" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetPointerUpListeners(view View, subviewID ...string) []func(View, PointerEvent) {
-	return getOneArgEventListeners[View, PointerEvent](view, subviewID, PointerUp)
+//
+// Result elements can be of the following types:
+//   - func(View, PointerEvent),
+//   - func(View),
+//   - func(PointerEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetPointerUpListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, PointerEvent](view, subviewID, PointerUp)
 }
 
 // GetPointerMoveListeners returns the "pointer-move" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetPointerMoveListeners(view View, subviewID ...string) []func(View, PointerEvent) {
-	return getOneArgEventListeners[View, PointerEvent](view, subviewID, PointerMove)
+//
+// Result elements can be of the following types:
+//   - func(View, PointerEvent),
+//   - func(View),
+//   - func(PointerEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetPointerMoveListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, PointerEvent](view, subviewID, PointerMove)
 }
 
 // GetPointerCancelListeners returns the "pointer-cancel" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetPointerCancelListeners(view View, subviewID ...string) []func(View, PointerEvent) {
-	return getOneArgEventListeners[View, PointerEvent](view, subviewID, PointerCancel)
+//
+// Result elements can be of the following types:
+//   - func(View, PointerEvent),
+//   - func(View),
+//   - func(PointerEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetPointerCancelListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, PointerEvent](view, subviewID, PointerCancel)
 }
 
 // GetPointerOverListeners returns the "pointer-over" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetPointerOverListeners(view View, subviewID ...string) []func(View, PointerEvent) {
-	return getOneArgEventListeners[View, PointerEvent](view, subviewID, PointerOver)
+//
+// Result elements can be of the following types:
+//   - func(View, PointerEvent),
+//   - func(View),
+//   - func(PointerEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetPointerOverListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, PointerEvent](view, subviewID, PointerOver)
 }
 
 // GetPointerOutListeners returns the "pointer-out" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetPointerOutListeners(view View, subviewID ...string) []func(View, PointerEvent) {
-	return getOneArgEventListeners[View, PointerEvent](view, subviewID, PointerOut)
+//
+// Result elements can be of the following types:
+//   - func(View, PointerEvent),
+//   - func(View),
+//   - func(PointerEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetPointerOutListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, PointerEvent](view, subviewID, PointerOut)
 }

popup.go

@@ -2,6 +2,7 @@ package rui
 
 import (
 	"fmt"
+	"reflect"
 	"strings"
 )
 
@@ -150,7 +151,7 @@ const (
 	//
 	// Used by Popup.
 	// Specify start translation, scale and rotation over x, y and z axes as well as a distortion
-	// for an animated Popup showing/hidding.
+	// for an animated Popup showing/hiding.
 	//
 	// Supported types: TransformProperty, string.
 	//
@@ -278,7 +279,24 @@ type Popup interface {
 	viewByHTMLID(id string) View
 	keyEvent(event KeyEvent) bool
 	showAnimation()
-	dissmissAnimation(listener func(PropertyName)) bool
+	dismissAnimation(listener func(PropertyName)) bool
+}
+
+type popupListener interface {
+	Run(Popup)
+	rawListener() any
+}
+
+type popupListener0 struct {
+	fn func()
+}
+
+type popupListener1 struct {
+	fn func(Popup)
+}
+
+type popupListenerBinding struct {
+	name string
 }
 
 type popupData struct {
@@ -287,7 +305,7 @@ type popupData struct {
 	contentView     View
 	buttons         []PopupButton
 	cancelable      bool
-	dismissListener []func(Popup)
+	dismissListener []popupListener
 	showTransform   TransformProperty
 	showOpacity     float64
 	showDuration    float64
@@ -649,7 +667,7 @@ func (popup *popupData) init(view View, popupParams Params) {
 				}
 
 			case DismissEvent:
-				if listeners, ok := valueToNoArgEventListeners[Popup](value); ok {
+				if listeners, ok := valueToPopupEventListeners(value); ok {
 					if listeners != nil {
 						popup.dismissListener = listeners
 					}
@@ -831,7 +849,7 @@ func (popup *popupData) showAnimation() {
 	}
 }
 
-func (popup *popupData) dissmissAnimation(listener func(PropertyName)) bool {
+func (popup *popupData) dismissAnimation(listener func(PropertyName)) bool {
 	if popup.showOpacity != 1 || popup.showTransform != nil {
 		session := popup.Session()
 		popup.popupView.Set(TransitionEndEvent, listener)
@@ -887,7 +905,7 @@ func (popup *popupData) onDismiss() {
 	popup.Session().callFunc("removeView", popup.layerView.htmlID())
 
 	for _, listener := range popup.dismissListener {
-		listener(popup)
+		listener.Run(popup)
 	}
 }
 
@@ -923,6 +941,25 @@ func NewPopup(view View, param Params) Popup {
 	return popup
 }
 
+/*
+func CreatePopupFromObject(session Session, object DataObject, binding any) Popup {
+	node := object.RemovePropertyByTag(string(Content))
+	if node == nil {
+		ErrorLog(`"content" property not found`)
+		return nil
+	}
+
+	switch node.Type() {
+	case ObjectNode:
+
+	case TextNode:
+
+	default:
+		ErrorLog(`Unsupported data of "content" property`)
+		return nil
+	}
+}
+*/
 // ShowPopup creates a new Popup and shows it
 func ShowPopup(view View, param Params) Popup {
 	popup := NewPopup(view, param)
@@ -994,23 +1031,162 @@ func (manager *popupManager) dismissPopup(popup Popup) {
 
 	session := popup.Session()
 	listener := func(PropertyName) {
-		if index == count-1 {
+		switch index {
+		case 0:
 			if count == 1 {
 				manager.popups = []Popup{}
 				session.updateCSSProperty("ruiRoot", "pointer-events", "auto")
 				session.updateCSSProperty("ruiPopupLayer", "visibility", "hidden")
 			} else {
-				manager.popups = manager.popups[:count-1]
+				manager.popups = manager.popups[1:]
 			}
-		} else if index == 0 {
-			manager.popups = manager.popups[1:]
-		} else {
+
+		case count - 1:
+			manager.popups = manager.popups[:count-1]
+
+		default:
 			manager.popups = append(manager.popups[:index], manager.popups[index+1:]...)
 		}
 		popup.onDismiss()
 	}
 
-	if !popup.dissmissAnimation(listener) {
+	if !popup.dismissAnimation(listener) {
 		listener("")
 	}
 }
+
+func newPopupListener0(fn func()) popupListener {
+	obj := new(popupListener0)
+	obj.fn = fn
+	return obj
+}
+
+func (data *popupListener0) Run(_ Popup) {
+	data.fn()
+}
+
+func (data *popupListener0) rawListener() any {
+	return data.fn
+}
+
+func newPopupListener1(fn func(Popup)) popupListener {
+	obj := new(popupListener1)
+	obj.fn = fn
+	return obj
+}
+
+func (data *popupListener1) Run(popup Popup) {
+	data.fn(popup)
+}
+
+func (data *popupListener1) rawListener() any {
+	return data.fn
+}
+
+func newPopupListenerBinding(name string) popupListener {
+	obj := new(popupListenerBinding)
+	obj.name = name
+	return obj
+}
+
+func (data *popupListenerBinding) Run(popup Popup) {
+	bind := popup.View().binding()
+	if bind == nil {
+		ErrorLogF(`There is no a binding object for call "%s"`, data.name)
+		return
+	}
+
+	val := reflect.ValueOf(bind)
+	method := val.MethodByName(data.name)
+	if !method.IsValid() {
+		ErrorLogF(`The "%s" method is not valid`, data.name)
+		return
+	}
+
+	methodType := method.Type()
+	var args []reflect.Value = nil
+	switch methodType.NumIn() {
+	case 0:
+		args = []reflect.Value{}
+
+	case 1:
+		inType := methodType.In(0)
+		if inType == reflect.TypeOf(popup) {
+			args = []reflect.Value{reflect.ValueOf(popup)}
+		}
+	}
+
+	if args != nil {
+		method.Call(args)
+	} else {
+		ErrorLogF(`Unsupported prototype of "%s" method`, data.name)
+	}
+}
+
+func (data *popupListenerBinding) rawListener() any {
+	return data.name
+}
+
+func valueToPopupEventListeners(value any) ([]popupListener, bool) {
+	if value == nil {
+		return nil, true
+	}
+
+	switch value := value.(type) {
+	case []popupListener:
+		return value, true
+
+	case popupListener:
+		return []popupListener{value}, true
+
+	case string:
+		return []popupListener{newPopupListenerBinding(value)}, true
+
+	case func(Popup):
+		return []popupListener{newPopupListener1(value)}, true
+
+	case func():
+		return []popupListener{newPopupListener0(value)}, true
+
+	case []func(Popup):
+		result := make([]popupListener, 0, len(value))
+		for _, fn := range value {
+			if fn != nil {
+				result = append(result, newPopupListener1(fn))
+			}
+		}
+		return result, len(result) > 0
+
+	case []func():
+		result := make([]popupListener, 0, len(value))
+		for _, fn := range value {
+			if fn != nil {
+				result = append(result, newPopupListener0(fn))
+			}
+		}
+		return result, len(result) > 0
+
+	case []any:
+		result := make([]popupListener, 0, len(value))
+		for _, v := range value {
+			if v != nil {
+				switch v := v.(type) {
+				case func(Popup):
+					result = append(result, newPopupListener1(v))
+
+				case func():
+					result = append(result, newPopupListener0(v))
+
+				case string:
+					result = append(result, newPopupListenerBinding(v))
+
+				default:
+					return nil, false
+				}
+			}
+		}
+		return result, len(result) > 0
+	}
+
+	return nil, false
+}

progressBar.go

@@ -101,13 +101,17 @@ func (progress *progressBarData) htmlProperties(self View, buffer *strings.Build
 }
 
 // GetProgressBarMax returns the max value of ProgressBar subview.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetProgressBarMax(view View, subviewID ...string) float64 {
 	return floatStyledProperty(view, subviewID, ProgressBarMax, 1)
 }
 
 // GetProgressBarValue returns the value of ProgressBar subview.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetProgressBarValue(view View, subviewID ...string) float64 {
 	return floatStyledProperty(view, subviewID, ProgressBarValue, 0)
 }

propertyNames.go

@@ -2723,4 +2723,6 @@ const (
 	//
 	// Supported types: string.
 	Tooltip PropertyName = "tooltip"
+
+	Binding PropertyName = "binding"
 )

resizable.go

@@ -118,7 +118,7 @@ func (resizable *resizableData) setFunc(tag PropertyName, value any) []PropertyN
 			newContent = value
 
 		case DataObject:
-			if newContent = CreateViewFromObject(resizable.Session(), value); newContent == nil {
+			if newContent = CreateViewFromObject(resizable.Session(), value, nil); newContent == nil {
 				return nil
 			}
 
@@ -354,7 +354,7 @@ func (resizable *resizableData) htmlSubviews(self View, buffer *strings.Builder)
 	}
 
 	writePos := func(x1, x2, y1, y2 int) {
-		buffer.WriteString(fmt.Sprintf(` grid-column-start: %d; grid-column-end: %d; grid-row-start: %d;  grid-row-end: %d;"></div>`, x1, x2, y1, y2))
+		fmt.Fprintf(buffer, ` grid-column-start: %d; grid-column-end: %d; grid-row-start: %d;  grid-row-end: %d;"></div>`, x1, x2, y1, y2)
 	}
 	//htmlID := resizable.htmlID()
 

resizeEvent.go

@@ -25,8 +25,8 @@ func (view *viewData) onResize(self View, x, y, width, height float64) {
 	view.frame.Top = y
 	view.frame.Width = width
 	view.frame.Height = height
-	for _, listener := range GetResizeListeners(view) {
-		listener(self, view.frame)
+	for _, listener := range getOneArgEventListeners[View, Frame](view, nil, ResizeEvent) {
+		listener.Run(self, view.frame)
 	}
 }
 
@@ -73,7 +73,9 @@ func (view *viewData) Frame() Frame {
 }
 
 // GetViewFrame returns the size and location of view's viewport.
-// If the second argument (subviewID) is not specified or it is "" then the value of the first argument (view) is returned
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetViewFrame(view View, subviewID ...string) Frame {
 	view = getSubview(view, subviewID)
 	if view == nil {
@@ -83,7 +85,16 @@ func GetViewFrame(view View, subviewID ...string) Frame {
 }
 
 // GetResizeListeners returns the list of "resize-event" listeners. If there are no listeners then the empty list is returned
-// If the second argument (subviewID) is not specified or it is "" then the listeners list of the first argument (view) is returned
-func GetResizeListeners(view View, subviewID ...string) []func(View, Frame) {
-	return getOneArgEventListeners[View, Frame](view, subviewID, ResizeEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.View, rui.Frame),
+//   - func(rui.View),
+//   - func(rui.Frame),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetResizeListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, Frame](view, subviewID, ResizeEvent)
 }

resources.go

@@ -401,7 +401,7 @@ func OpenRawResource(filename string) fs.File {
 	return nil
 }
 
-// AllRawResources returns the list of all raw resouces
+// AllRawResources returns the list of all raw resources
 func AllRawResources() []string {
 	result := []string{}
 
@@ -448,7 +448,7 @@ func AllRawResources() []string {
 	return result
 }
 
-// AllImageResources returns the list of all image resouces
+// AllImageResources returns the list of all image resources
 func AllImageResources() []string {
 	result := make([]string, 0, len(resources.images))
 	for image := range resources.images {

scrollEvent.go

@@ -25,8 +25,8 @@ func (view *viewData) onScroll(self View, x, y, width, height float64) {
 	view.scroll.Top = y
 	view.scroll.Width = width
 	view.scroll.Height = height
-	for _, listener := range GetScrollListeners(view) {
-		listener(self, view.scroll)
+	for _, listener := range getOneArgEventListeners[View, Frame](view, nil, ScrollEvent) {
+		listener.Run(self, view.scroll)
 	}
 }
 
@@ -42,7 +42,9 @@ func (view *viewData) setScroll(x, y, width, height float64) {
 }
 
 // GetViewScroll returns ...
-// If the second argument (subviewID) is not specified or it is "" then a value of the first argument (view) is returned
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetViewScroll(view View, subviewID ...string) Frame {
 	view = getSubview(view, subviewID)
 	if view == nil {
@@ -52,13 +54,24 @@ func GetViewScroll(view View, subviewID ...string) Frame {
 }
 
 // GetScrollListeners returns the list of "scroll-event" listeners. If there are no listeners then the empty list is returned
-// If the second argument (subviewID) is not specified or it is "" then the listeners list of the first argument (view) is returned
-func GetScrollListeners(view View, subviewID ...string) []func(View, Frame) {
-	return getOneArgEventListeners[View, Frame](view, subviewID, ResizeEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.View, rui.Frame),
+//   - func(rui.View),
+//   - func(rui.Frame),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetScrollListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, Frame](view, subviewID, ScrollEvent)
 }
 
 // ScrollTo scrolls the view's content to the given position.
-// If the second argument (subviewID) is "" then the first argument (view) is used
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func ScrollViewTo(view View, subviewID string, x, y float64) {
 	if subviewID != "" {
 		view = ViewByID(view, subviewID)
@@ -69,7 +82,9 @@ func ScrollViewTo(view View, subviewID string, x, y float64) {
 }
 
 // ScrollViewToEnd scrolls the view's content to the start of view.
-// If the second argument (subviewID) is not specified or it is "" then the first argument (view) is used
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func ScrollViewToStart(view View, subviewID ...string) {
 	if view = getSubview(view, subviewID); view != nil {
 		view.Session().callFunc("scrollToStart", view.htmlID())
@@ -77,7 +92,9 @@ func ScrollViewToStart(view View, subviewID ...string) {
 }
 
 // ScrollViewToEnd scrolls the view's content to the end of view.
-// If the second argument (subviewID) is not specified or it is "" then the first argument (view) is used
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func ScrollViewToEnd(view View, subviewID ...string) {
 	if view = getSubview(view, subviewID); view != nil {
 		view.Session().callFunc("scrollToEnd", view.htmlID())

session.go

@@ -266,7 +266,8 @@ func (session *sessionData) setBridge(events chan DataObject, bridge bridge) {
 
 func (session *sessionData) close() {
 	if session.events != nil {
-		session.events <- ParseDataText(`session-close{session="` + strconv.Itoa(session.sessionID) + `"}`)
+		obj, _ := ParseDataText(`session-close{session="` + strconv.Itoa(session.sessionID) + `"}`)
+		session.events <- obj
 	}
 }
 

sizeFunc.go

@@ -208,7 +208,7 @@ func (data *sizeFuncData) writeString(topFunc string, buffer *strings.Builder) {
 			buffer.WriteString(arg.String())
 
 		case float64:
-			buffer.WriteString(fmt.Sprintf("%g", arg))
+			fmt.Fprintf(buffer, "%g", arg)
 		}
 
 	}
@@ -302,7 +302,7 @@ func (data *sizeFuncData) writeCSS(topFunc string, buffer *strings.Builder, sess
 			buffer.WriteString(arg.String())
 
 		case float64:
-			buffer.WriteString(fmt.Sprintf("%g", arg))
+			fmt.Fprintf(buffer, "%g", arg)
 		}
 
 	}

stackLayout.go

@@ -334,7 +334,9 @@ func (layout *stackLayoutData) init(session Session) {
 	layout.remove = layout.removeFunc
 	layout.changed = layout.propertyChanged
 
-	layout.setRaw(TransitionEndEvent, []func(View, PropertyName){layout.transitionFinished})
+	layout.setRaw(TransitionEndEvent, []oneArgListener[View, PropertyName]{
+		newOneArgListenerVE(layout.transitionFinished),
+	})
 	if session.TextDirection() == RightToLeftDirection {
 		layout.setRaw(PushTransform, NewTransformProperty(Params{TranslateX: Percent(-100)}))
 	} else {
@@ -434,7 +436,7 @@ func (layout *stackLayoutData) setFunc(tag PropertyName, value any) []PropertyNa
 		// TODO
 		listeners, ok := valueToOneArgEventListeners[View, PropertyName](value)
 		if ok && listeners != nil {
-			listeners = append(listeners, layout.transitionFinished)
+			listeners = append(listeners, newOneArgListenerVE(layout.transitionFinished))
 			layout.setRaw(TransitionEndEvent, listeners)
 			return []PropertyName{tag}
 		}
@@ -464,7 +466,9 @@ func (layout *stackLayoutData) propertyChanged(tag PropertyName) {
 func (layout *stackLayoutData) removeFunc(tag PropertyName) []PropertyName {
 	switch tag {
 	case TransitionEndEvent:
-		layout.setRaw(TransitionEndEvent, []func(View, PropertyName){layout.transitionFinished})
+		layout.setRaw(TransitionEndEvent, []oneArgListener[View, PropertyName]{
+			newOneArgListenerVE(layout.transitionFinished),
+		})
 		return []PropertyName{tag}
 	}
 	return layout.viewsContainerData.removeFunc(tag)
@@ -606,12 +610,6 @@ func (layout *stackLayoutData) moveToFrontByIndex(index int, onShow []func(View)
 	session.updateCSSProperty(peekPageID, "transform", transformCSS)
 }
 
-func (layout *stackLayoutData) contentChanged() {
-	if listener, ok := layout.changeListener[Content]; ok {
-		listener(layout, Content)
-	}
-}
-
 func (layout *stackLayoutData) RemovePeek() View {
 	return layout.RemoveView(len(layout.views) - 1)
 }
@@ -679,9 +677,7 @@ func (layout *stackLayoutData) Append(view View) {
 		}
 		session.appendToInnerHTML(stackID, buffer.String())
 
-		if listener, ok := layout.changeListener[Content]; ok {
-			listener(layout, Content)
-		}
+		layout.contentChanged()
 	}
 }
 
@@ -717,9 +713,7 @@ func (layout *stackLayoutData) Insert(view View, index int) {
 	session := layout.Session()
 	session.appendToInnerHTML(stackID, buffer.String())
 
-	if listener, ok := layout.changeListener[Content]; ok {
-		listener(layout, Content)
-	}
+	layout.contentChanged()
 }
 
 // Remove removes view from list and return it
@@ -750,10 +744,7 @@ func (layout *stackLayoutData) RemoveView(index int) View {
 	}
 
 	layout.Session().callFunc("removeView", view.htmlID()+"page")
-
-	if listener, ok := layout.changeListener[Content]; ok {
-		listener(layout, Content)
-	}
+	layout.contentChanged()
 	return view
 }
 
@@ -914,7 +905,9 @@ func (layout *stackLayoutData) htmlSubviews(self View, buffer *strings.Builder)
 }
 
 // IsMoveToFrontAnimation returns "true" if an animation is used when calling the MoveToFront/MoveToFrontByID method of StackLayout interface.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func IsMoveToFrontAnimation(view View, subviewID ...string) bool {
 	if view = getSubview(view, subviewID); view != nil {
 		if value, ok := boolProperty(view, MoveToFrontAnimation, view.Session()); ok {
@@ -950,7 +943,9 @@ func GetPushTiming(view View, subviewID ...string) string {
 // GetPushTransform returns the start transform (translation, scale and rotation over x, y and z axes as well as a distortion)
 // for an animated pushing of a child view.
 // The default value is nil (no transform).
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetPushTransform(view View, subviewID ...string) TransformProperty {
 	return transformStyledProperty(view, subviewID, PushTransform)
 }

strings.go

@@ -50,8 +50,9 @@ func (resources *resourceManager) scanStringsDir(path string) {
 }
 
 func loadStringResources(text string) {
-	data := ParseDataText(text)
-	if data == nil {
+	data, err := ParseDataText(text)
+	if err != nil {
+		ErrorLog(err.Error())
 		return
 	}
 

tableView.go

@@ -592,14 +592,6 @@ func (table *tableViewData) init(session Session) {
 	table.tag = "TableView"
 	table.cellViews = []View{}
 	table.cellFrame = []Frame{}
-	/*
-		table.cellSelectedListener = []func(TableView, int, int){}
-		table.cellClickedListener = []func(TableView, int, int){}
-		table.rowSelectedListener = []func(TableView, int){}
-		table.rowClickedListener = []func(TableView, int){}
-		table.current.Row = -1
-		table.current.Column = -1
-	*/
 	table.normalize = normalizeTableViewTag
 	table.set = table.setFunc
 	table.changed = table.propertyChanged
@@ -853,8 +845,17 @@ func (table *tableViewData) propertyChanged(tag PropertyName) {
 			current := tableViewCurrent(table)
 			session.callFunc("setTableCellCursorByID", htmlID, current.Row, current.Column)
 
+			for _, listener := range getTwoArgEventListeners[TableView, int](table, nil, TableCellSelectedEvent) {
+				listener.Run(table, current.Row, current.Column)
+			}
+
 		case RowSelection:
-			session.callFunc("setTableRowCursorByID", htmlID, tableViewCurrent(table).Row)
+			current := tableViewCurrent(table)
+			session.callFunc("setTableRowCursorByID", htmlID, current.Row)
+
+			for _, listener := range getOneArgEventListeners[TableView, int](table, nil, TableRowSelectedEvent) {
+				listener.Run(table, current.Row)
+			}
 		}
 
 	case Gap:
@@ -955,63 +956,6 @@ func tableViewCurrentInactiveStyle(view View) string {
 	return "ruiCurrentTableCell"
 }
 
-/*
-func (table *tableViewData) valueToCellListeners(value any) []func(TableView, int, int) {
-	if value == nil {
-		return []func(TableView, int, int){}
-	}
-
-	switch value := value.(type) {
-	case func(TableView, int, int):
-		return []func(TableView, int, int){value}
-
-	case func(int, int):
-		fn := func(_ TableView, row, column int) {
-			value(row, column)
-		}
-		return []func(TableView, int, int){fn}
-
-	case []func(TableView, int, int):
-		return value
-
-	case []func(int, int):
-		listeners := make([]func(TableView, int, int), len(value))
-		for i, val := range value {
-			if val == nil {
-				return nil
-			}
-			listeners[i] = func(_ TableView, row, column int) {
-				val(row, column)
-			}
-		}
-		return listeners
-
-	case []any:
-		listeners := make([]func(TableView, int, int), len(value))
-		for i, val := range value {
-			if val == nil {
-				return nil
-			}
-			switch val := val.(type) {
-			case func(TableView, int, int):
-				listeners[i] = val
-
-			case func(int, int):
-				listeners[i] = func(_ TableView, row, column int) {
-					val(row, column)
-				}
-
-			default:
-				return nil
-			}
-		}
-		return listeners
-	}
-
-	return nil
-}
-*/
-
 func (table *tableViewData) htmlTag() string {
 	return "table"
 }
@@ -1326,10 +1270,10 @@ func (table *tableViewData) htmlSubviews(self View, buffer *strings.Builder) {
 							buffer.WriteString(string(value))
 
 						case float32:
-							buffer.WriteString(fmt.Sprintf("%g", float64(value)))
+							fmt.Fprintf(buffer, "%g", float64(value))
 
 						case float64:
-							buffer.WriteString(fmt.Sprintf("%g", value))
+							fmt.Fprintf(buffer, "%g", value)
 
 						case bool:
 							if value {
@@ -1340,7 +1284,7 @@ func (table *tableViewData) htmlSubviews(self View, buffer *strings.Builder) {
 
 						default:
 							if n, ok := isInt(value); ok {
-								buffer.WriteString(fmt.Sprintf("%d", n))
+								fmt.Fprintf(buffer, "%d", n)
 							} else {
 								buffer.WriteString("<Unsupported value>")
 							}
@@ -1359,7 +1303,7 @@ func (table *tableViewData) htmlSubviews(self View, buffer *strings.Builder) {
 
 	if columnStyle := GetTableColumnStyle(table); columnStyle != nil {
 		buffer.WriteString("<colgroup>")
-		for column := 0; column < columnCount; column++ {
+		for column := range columnCount {
 			cssBuilder.buffer.Reset()
 			if styles := columnStyle.ColumnStyle(column); styles != nil {
 				view.Clear()
@@ -1593,10 +1537,10 @@ func (table *tableViewData) writeCellHtml(adapter TableAdapter, row, column int,
 		buffer.WriteString(string(value))
 
 	case float32:
-		buffer.WriteString(fmt.Sprintf("%g", float64(value)))
+		fmt.Fprintf(buffer, "%g", float64(value))
 
 	case float64:
-		buffer.WriteString(fmt.Sprintf("%g", value))
+		fmt.Fprintf(buffer, "%g", value)
 
 	case bool:
 		accentColor := Color(0)
@@ -1611,7 +1555,7 @@ func (table *tableViewData) writeCellHtml(adapter TableAdapter, row, column int,
 
 	default:
 		if n, ok := isInt(value); ok {
-			buffer.WriteString(fmt.Sprintf("%d", n))
+			fmt.Fprintf(buffer, "%d", n)
 		} else {
 			buffer.WriteString("<Unsupported value>")
 		}
@@ -1732,11 +1676,11 @@ func (table *tableViewData) handleCommand(self View, command PropertyName, data
 			current.Row = row
 			table.setRaw(Current, current.Row)
 			if listener, ok := table.changeListener[Current]; ok {
-				listener(table, Current)
+				listener.Run(table, Current)
 			}
 
-			for _, listener := range GetTableRowSelectedListeners(table) {
-				listener(table, row)
+			for _, listener := range getOneArgEventListeners[TableView, int](table, nil, TableRowSelectedEvent) {
+				listener.Run(table, row)
 			}
 		}
 
@@ -1749,11 +1693,11 @@ func (table *tableViewData) handleCommand(self View, command PropertyName, data
 					current.Column = column
 					table.setRaw(Current, current.Row)
 					if listener, ok := table.changeListener[Current]; ok {
-						listener(table, Current)
+						listener.Run(table, Current)
 					}
 
-					for _, listener := range GetTableCellSelectedListeners(table) {
-						listener(table, row, column)
+					for _, listener := range getTwoArgEventListeners[TableView, int](table, nil, TableCellSelectedEvent) {
+						listener.Run(table, row, column)
 					}
 				}
 			}
@@ -1761,16 +1705,16 @@ func (table *tableViewData) handleCommand(self View, command PropertyName, data
 
 	case "rowClick":
 		if row, ok := dataIntProperty(data, "row"); ok {
-			for _, listener := range GetTableRowClickedListeners(table) {
-				listener(table, row)
+			for _, listener := range getOneArgEventListeners[TableView, int](table, nil, TableRowClickedEvent) {
+				listener.Run(table, row)
 			}
 		}
 
 	case "cellClick":
 		if row, ok := dataIntProperty(data, "row"); ok {
 			if column, ok := dataIntProperty(data, "column"); ok {
-				for _, listener := range GetTableCellClickedListeners(table) {
-					listener(table, row, column)
+				for _, listener := range getTwoArgEventListeners[TableView, int](table, nil, TableCellClickedEvent) {
+					listener.Run(table, row, column)
 				}
 			}
 		}

tableViewUtils.go

@@ -26,7 +26,9 @@ func (cell *tableCellView) cssStyle(self View, builder cssBuilder) {
 }
 
 // GetTableContent returns a TableAdapter which defines the TableView content.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTableContent(view View, subviewID ...string) TableAdapter {
 	if view = getSubview(view, subviewID); view != nil {
 		if content := view.getRaw(Content); content != nil {
@@ -40,7 +42,9 @@ func GetTableContent(view View, subviewID ...string) TableAdapter {
 }
 
 // GetTableRowStyle returns a TableRowStyle which defines styles of TableView rows.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTableRowStyle(view View, subviewID ...string) TableRowStyle {
 	if view = getSubview(view, subviewID); view != nil {
 		for _, tag := range []PropertyName{RowStyle, Content} {
@@ -56,7 +60,9 @@ func GetTableRowStyle(view View, subviewID ...string) TableRowStyle {
 }
 
 // GetTableColumnStyle returns a TableColumnStyle which defines styles of TableView columns.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTableColumnStyle(view View, subviewID ...string) TableColumnStyle {
 	if view = getSubview(view, subviewID); view != nil {
 		for _, tag := range []PropertyName{ColumnStyle, Content} {
@@ -72,7 +78,9 @@ func GetTableColumnStyle(view View, subviewID ...string) TableColumnStyle {
 }
 
 // GetTableCellStyle returns a TableCellStyle which defines styles of TableView cells.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTableCellStyle(view View, subviewID ...string) TableCellStyle {
 	if view = getSubview(view, subviewID); view != nil {
 		for _, tag := range []PropertyName{CellStyle, Content} {
@@ -90,26 +98,34 @@ func GetTableCellStyle(view View, subviewID ...string) TableCellStyle {
 
 // GetTableSelectionMode returns the mode of the TableView elements selection.
 // Valid values are NoneSelection (0), CellSelection (1), and RowSelection (2).
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTableSelectionMode(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, SelectionMode, NoneSelection, false)
 }
 
 // GetTableVerticalAlign returns a vertical align in a TableView cell. Returns one of next values:
 // TopAlign (0), BottomAlign (1), CenterAlign (2), and BaselineAlign (3)
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTableVerticalAlign(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, TableVerticalAlign, TopAlign, false)
 }
 
 // GetTableHeadHeight returns the number of rows in the table header.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTableHeadHeight(view View, subviewID ...string) int {
 	return intStyledProperty(view, subviewID, HeadHeight, 0)
 }
 
 // GetTableFootHeight returns the number of rows in the table footer.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTableFootHeight(view View, subviewID ...string) int {
 	return intStyledProperty(view, subviewID, FootHeight, 0)
 }
@@ -118,7 +134,9 @@ func GetTableFootHeight(view View, subviewID ...string) int {
 // If there is no selected cell/row or the selection mode is NoneSelection (0),
 // then a value of the row and column index less than 0 is returned.
 // If the selection mode is RowSelection (2) then the returned column index is less than 0.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTableCurrent(view View, subviewID ...string) CellIndex {
 	if view = getSubview(view, subviewID); view != nil {
 		if selectionMode := GetTableSelectionMode(view); selectionMode != NoneSelection {
@@ -130,30 +148,70 @@ func GetTableCurrent(view View, subviewID ...string) CellIndex {
 
 // GetTableCellClickedListeners returns listeners of event which occurs when the user clicks on a table cell.
 // If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetTableCellClickedListeners(view View, subviewID ...string) []func(TableView, int, int) {
-	return getTwoArgEventListeners[TableView, int](view, subviewID, TableCellClickedEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.TableView, int, int),
+//   - func(rui.TableView, int),
+//   - func(rui.TableView),
+//   - func(int, int),
+//   - func(int),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetTableCellClickedListeners(view View, subviewID ...string) []any {
+	return getTwoArgEventRawListeners[TableView, int](view, subviewID, TableCellClickedEvent)
 }
 
 // GetTableCellSelectedListeners returns listeners of event which occurs when a table cell becomes selected.
 // If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetTableCellSelectedListeners(view View, subviewID ...string) []func(TableView, int, int) {
-	return getTwoArgEventListeners[TableView, int](view, subviewID, TableCellSelectedEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.TableView, int, int),
+//   - func(rui.TableView, int),
+//   - func(rui.TableView),
+//   - func(int, int),
+//   - func(int),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetTableCellSelectedListeners(view View, subviewID ...string) []any {
+	return getTwoArgEventRawListeners[TableView, int](view, subviewID, TableCellSelectedEvent)
 }
 
 // GetTableRowClickedListeners returns listeners of event which occurs when the user clicks on a table row.
 // If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetTableRowClickedListeners(view View, subviewID ...string) []func(TableView, int) {
-	return getOneArgEventListeners[TableView, int](view, subviewID, TableRowClickedEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.TableView, int),
+//   - func(rui.TableView),
+//   - func(int),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetTableRowClickedListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[TableView, int](view, subviewID, TableRowClickedEvent)
 }
 
 // GetTableRowSelectedListeners returns listeners of event which occurs when a table row becomes selected.
 // If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetTableRowSelectedListeners(view View, subviewID ...string) []func(TableView, int) {
-	return getOneArgEventListeners[TableView, int](view, subviewID, TableRowSelectedEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.TableView, int),
+//   - func(rui.TableView),
+//   - func(int),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetTableRowSelectedListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[TableView, int](view, subviewID, TableRowSelectedEvent)
 }
 
 // ReloadTableViewData updates TableView

tabsLayout.go

@@ -211,7 +211,7 @@ func (tabsLayout *tabsLayoutData) propertyChanged(tag PropertyName) {
 		if listeners := getTwoArgEventListeners[TabsLayout, int](tabsLayout, nil, CurrentTabChangedEvent); len(listeners) > 0 {
 			oldCurrent, _ := intProperty(tabsLayout, "old-current", session, -1)
 			for _, listener := range listeners {
-				listener(tabsLayout, current, oldCurrent)
+				listener.Run(tabsLayout, current, oldCurrent)
 			}
 		}
 
@@ -238,155 +238,6 @@ func (tabsLayout *tabsLayoutData) propertyChanged(tag PropertyName) {
 	}
 }
 
-/*
-	func (tabsLayout *tabsLayoutData) valueToTabListeners(value any) []func(TabsLayout, int, int) {
-		if value == nil {
-			return []func(TabsLayout, int, int){}
-		}
-
-		switch value := value.(type) {
-		case func(TabsLayout, int, int):
-			return []func(TabsLayout, int, int){value}
-
-		case func(TabsLayout, int):
-			fn := func(view TabsLayout, current, _ int) {
-				value(view, current)
-			}
-			return []func(TabsLayout, int, int){fn}
-
-		case func(TabsLayout):
-			fn := func(view TabsLayout, _, _ int) {
-				value(view)
-			}
-			return []func(TabsLayout, int, int){fn}
-
-		case func(int, int):
-			fn := func(_ TabsLayout, current, old int) {
-				value(current, old)
-			}
-			return []func(TabsLayout, int, int){fn}
-
-		case func(int):
-			fn := func(_ TabsLayout, current, _ int) {
-				value(current)
-			}
-			return []func(TabsLayout, int, int){fn}
-
-		case func():
-			fn := func(TabsLayout, int, int) {
-				value()
-			}
-			return []func(TabsLayout, int, int){fn}
-
-		case []func(TabsLayout, int, int):
-			return value
-
-		case []func(TabsLayout, int):
-			listeners := make([]func(TabsLayout, int, int), len(value))
-			for i, val := range value {
-				if val == nil {
-					return nil
-				}
-				listeners[i] = func(view TabsLayout, current, _ int) {
-					val(view, current)
-				}
-			}
-			return listeners
-
-		case []func(TabsLayout):
-			listeners := make([]func(TabsLayout, int, int), len(value))
-			for i, val := range value {
-				if val == nil {
-					return nil
-				}
-				listeners[i] = func(view TabsLayout, _, _ int) {
-					val(view)
-				}
-			}
-			return listeners
-
-		case []func(int, int):
-			listeners := make([]func(TabsLayout, int, int), len(value))
-			for i, val := range value {
-				if val == nil {
-					return nil
-				}
-				listeners[i] = func(_ TabsLayout, current, old int) {
-					val(current, old)
-				}
-			}
-			return listeners
-
-		case []func(int):
-			listeners := make([]func(TabsLayout, int, int), len(value))
-			for i, val := range value {
-				if val == nil {
-					return nil
-				}
-				listeners[i] = func(_ TabsLayout, current, _ int) {
-					val(current)
-				}
-			}
-			return listeners
-
-		case []func():
-			listeners := make([]func(TabsLayout, int, int), len(value))
-			for i, val := range value {
-				if val == nil {
-					return nil
-				}
-				listeners[i] = func(TabsLayout, int, int) {
-					val()
-				}
-			}
-			return listeners
-
-		case []any:
-			listeners := make([]func(TabsLayout, int, int), len(value))
-			for i, val := range value {
-				if val == nil {
-					return nil
-				}
-				switch val := val.(type) {
-				case func(TabsLayout, int, int):
-					listeners[i] = val
-
-				case func(TabsLayout, int):
-					listeners[i] = func(view TabsLayout, current, _ int) {
-						val(view, current)
-					}
-
-				case func(TabsLayout):
-					listeners[i] = func(view TabsLayout, _, _ int) {
-						val(view)
-					}
-
-				case func(int, int):
-					listeners[i] = func(_ TabsLayout, current, old int) {
-						val(current, old)
-					}
-
-				case func(int):
-					listeners[i] = func(_ TabsLayout, current, _ int) {
-						val(current)
-					}
-
-				case func():
-					listeners[i] = func(TabsLayout, int, int) {
-						val()
-					}
-
-				default:
-					return nil
-				}
-			}
-			return listeners
-		}
-
-		return nil
-	}
-*/
-
 func (tabsLayout *tabsLayoutData) tabsLocation() int {
 	tabs, _ := enumProperty(tabsLayout, Tabs, tabsLayout.session, 0)
 	return tabs
@@ -504,7 +355,7 @@ func (tabsLayout *tabsLayoutData) ListItem(index int, session Session) View {
 			Content: "✕",
 			ClickEvent: func() {
 				for _, listener := range getOneArgEventListeners[TabsLayout, int](tabsLayout, nil, TabCloseEvent) {
-					listener(tabsLayout, index)
+					listener.Run(tabsLayout, index)
 				}
 			},
 		}))
@@ -552,9 +403,7 @@ func (tabsLayout *tabsLayoutData) Append(view View) {
 		view.SetChangeListener(TabCloseButton, tabsLayout.updateTabCloseButton)
 		if tabsLayout.created {
 			updateInnerHTML(tabsLayout.htmlID(), tabsLayout.Session())
-			if listener, ok := tabsLayout.changeListener[Content]; ok {
-				listener(tabsLayout, Content)
-			}
+			tabsLayout.contentChanged()
 			tabsLayout.Set(Current, len(tabsLayout.views)-1)
 		}
 	}
@@ -576,11 +425,9 @@ func (tabsLayout *tabsLayoutData) Insert(view View, index int) {
 
 func (tabsLayout *tabsLayoutData) currentChanged(newCurrent, oldCurrent int) {
 	for _, listener := range getTwoArgEventListeners[TabsLayout, int](tabsLayout, nil, CurrentTabChangedEvent) {
-		listener(tabsLayout, newCurrent, oldCurrent)
-	}
-	if listener, ok := tabsLayout.changeListener[Current]; ok {
-		listener(tabsLayout, Current)
+		listener.Run(tabsLayout, newCurrent, oldCurrent)
 	}
+	tabsLayout.contentChanged()
 }
 
 // Remove removes view from list and return it
@@ -606,9 +453,7 @@ func (tabsLayout *tabsLayoutData) RemoveView(index int) View {
 				tabsLayout.Set(Current, newCurrent)
 			}
 			updateInnerHTML(tabsLayout.htmlID(), tabsLayout.Session())
-			if listener, ok := tabsLayout.changeListener[Content]; ok {
-				listener(tabsLayout, Content)
-			}
+			tabsLayout.contentChanged()
 		} else if newCurrent != oldCurrent {
 			tabsLayout.setRaw(Current, newCurrent)
 		}
@@ -892,7 +737,7 @@ func (tabsLayout *tabsLayoutData) handleCommand(self View, command PropertyName,
 		if numberText, ok := data.PropertyValue("number"); ok {
 			if number, err := strconv.Atoi(numberText); err == nil {
 				for _, listener := range getOneArgEventListeners[TabsLayout, int](tabsLayout, nil, TabCloseEvent) {
-					listener(tabsLayout, number)
+					listener.Run(tabsLayout, number)
 				}
 			}
 		}
@@ -900,3 +745,35 @@ func (tabsLayout *tabsLayoutData) handleCommand(self View, command PropertyName,
 	}
 	return tabsLayout.viewsContainerData.handleCommand(self, command, data)
 }
+
+// GetTabCloseEventListeners returns the "tab-close-event" listener list. If there are no listeners then the empty list is returned.
+//
+// Result elements can be of the following types:
+//   - func(rui.TabsLayout, int),
+//   - func(rui.TabsLayout),
+//   - func(int),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetTabCloseEventListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[TabsLayout, int](view, subviewID, TabCloseEvent)
+}
+
+// GetCurrentTabChangedEventListeners returns the "current-tab-changed" listener list. If there are no listeners then the empty list is returned.
+//
+// Result elements can be of the following types:
+//   - func(rui.TabsLayout, int, int),
+//   - func(rui.TabsLayout, int),
+//   - func(rui.TabsLayout),
+//   - func(int, int),
+//   - func(int),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetCurrentTabChangedEventListeners(view View, subviewID ...string) []any {
+	return getTwoArgEventRawListeners[TabsLayout, int](view, subviewID, CurrentTabChangedEvent)
+}

textView.go

@@ -111,7 +111,9 @@ func (textView *textViewData) htmlSubviews(self View, buffer *strings.Builder) {
 
 // GetTextOverflow returns a value of the "text-overflow" property:
 // TextOverflowClip (0) or TextOverflowEllipsis (1).
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTextOverflow(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, TextOverflow, SingleLineText, false)
 }

theme.go

@@ -686,8 +686,11 @@ func (theme *theme) addText(themeText string) bool {
 		theme.init()
 	}
 
-	data := ParseDataText(themeText)
-	if data == nil || !data.IsObject() || data.Tag() != "theme" {
+	data, err := ParseDataText(themeText)
+	if err != nil {
+		ErrorLog(err.Error())
+		return false
+	} else if !data.IsObject() || data.Tag() != "theme" {
 		return false
 	}
 
@@ -975,10 +978,10 @@ func (theme *theme) String() string {
 			buffer.WriteString(":landscape")
 		}
 		if maxWidth > 0 {
-			buffer.WriteString(fmt.Sprintf(":width%d", maxWidth))
+			fmt.Fprintf(buffer, ":width%d", maxWidth)
 		}
 		if maxHeight > 0 {
-			buffer.WriteString(fmt.Sprintf(":height%d", maxHeight))
+			fmt.Fprintf(buffer, ":height%d", maxHeight)
 		}
 		buffer.WriteString(" = [\n")
 
@@ -1014,21 +1017,21 @@ func (theme *theme) String() string {
 			}
 
 			if media.MinWidth > 0 {
-				buffer.WriteString(fmt.Sprintf(":width%d-", media.MinWidth))
+				fmt.Fprintf(buffer, ":width%d-", media.MinWidth)
 				if media.MaxWidth > 0 {
 					buffer.WriteString(strconv.Itoa(media.MaxWidth))
 				}
 			} else if media.MaxWidth > 0 {
-				buffer.WriteString(fmt.Sprintf(":width%d", media.MaxWidth))
+				fmt.Fprintf(buffer, ":width%d", media.MaxWidth)
 			}
 
 			if media.MinHeight > 0 {
-				buffer.WriteString(fmt.Sprintf(":height%d-", media.MinHeight))
+				fmt.Fprintf(buffer, ":height%d-", media.MinHeight)
 				if media.MaxHeight > 0 {
 					buffer.WriteString(strconv.Itoa(media.MaxHeight))
 				}
 			} else if media.MaxHeight > 0 {
-				buffer.WriteString(fmt.Sprintf(":height%d", media.MaxHeight))
+				fmt.Fprintf(buffer, ":height%d", media.MaxHeight)
 			}
 
 			buffer.WriteString(" = [\n")

timePicker.go

@@ -246,7 +246,7 @@ func (picker *timePickerData) propertyChanged(tag PropertyName) {
 		value := GetTimePickerValue(picker)
 		session.callFunc("setInputValue", picker.htmlID(), value.Format(timeFormat))
 
-		if listeners := GetTimeChangedListeners(picker); len(listeners) > 0 {
+		if listeners := getTwoArgEventListeners[TimePicker, time.Time](picker, nil, TimeChangedEvent); len(listeners) > 0 {
 			oldTime := time.Now()
 			if val := picker.getRaw("old-time"); val != nil {
 				if time, ok := val.(time.Time); ok {
@@ -254,7 +254,7 @@ func (picker *timePickerData) propertyChanged(tag PropertyName) {
 				}
 			}
 			for _, listener := range listeners {
-				listener(picker, value, oldTime)
+				listener.Run(picker, value, oldTime)
 			}
 		}
 
@@ -320,11 +320,11 @@ func (picker *timePickerData) handleCommand(self View, command PropertyName, dat
 				oldValue := GetTimePickerValue(picker)
 				picker.properties[TimePickerValue] = value
 				if value != oldValue {
-					for _, listener := range GetTimeChangedListeners(picker) {
-						listener(picker, value, oldValue)
+					for _, listener := range getTwoArgEventListeners[TimePicker, time.Time](picker, nil, TimeChangedEvent) {
+						listener.Run(picker, value, oldValue)
 					}
 					if listener, ok := picker.changeListener[TimePickerValue]; ok {
-						listener(picker, TimePickerValue)
+						listener.Run(picker, TimePickerValue)
 					}
 
 				}
@@ -373,7 +373,9 @@ func getTimeProperty(view View, mainTag, shortTag PropertyName) (time.Time, bool
 
 // GetTimePickerMin returns the min time of TimePicker subview and "true" as the second value if the min time is set,
 // "false" as the second value otherwise.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTimePickerMin(view View, subviewID ...string) (time.Time, bool) {
 	if view = getSubview(view, subviewID); view != nil {
 		return getTimeProperty(view, TimePickerMin, Min)
@@ -383,7 +385,9 @@ func GetTimePickerMin(view View, subviewID ...string) (time.Time, bool) {
 
 // GetTimePickerMax returns the max time of TimePicker subview and "true" as the second value if the min time is set,
 // "false" as the second value otherwise.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTimePickerMax(view View, subviewID ...string) (time.Time, bool) {
 	if view = getSubview(view, subviewID); view != nil {
 		return getTimeProperty(view, TimePickerMax, Max)
@@ -392,13 +396,17 @@ func GetTimePickerMax(view View, subviewID ...string) (time.Time, bool) {
 }
 
 // GetTimePickerStep returns the time changing step in seconds of TimePicker subview.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTimePickerStep(view View, subviewID ...string) int {
 	return intStyledProperty(view, subviewID, TimePickerStep, 60)
 }
 
 // GetTimePickerValue returns the time of TimePicker subview.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTimePickerValue(view View, subviewID ...string) time.Time {
 	if view = getSubview(view, subviewID); view == nil {
 		return time.Now()
@@ -409,7 +417,18 @@ func GetTimePickerValue(view View, subviewID ...string) time.Time {
 
 // GetTimeChangedListeners returns the TimeChangedListener list of an TimePicker subview.
 // If there are no listeners then the empty list is returned
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetTimeChangedListeners(view View, subviewID ...string) []func(TimePicker, time.Time, time.Time) {
-	return getTwoArgEventListeners[TimePicker, time.Time](view, subviewID, TimeChangedEvent)
+//
+// Result elements can be of the following types:
+//   - func(rui.TimePicker, time.Time, time.Time),
+//   - func(rui.TimePicker, time.Time),
+//   - func(rui.TimePicker),
+//   - func(time.Time, time.Time),
+//   - func(time.Time),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetTimeChangedListeners(view View, subviewID ...string) []any {
+	return getTwoArgEventRawListeners[TimePicker, time.Time](view, subviewID, TimeChangedEvent)
 }

touchEvents.go

@@ -193,30 +193,66 @@ func handleTouchEvents(view View, tag PropertyName, data DataObject) {
 	event.init(data)
 
 	for _, listener := range listeners {
-		listener(view, event)
+		listener.Run(view, event)
 	}
 }
 
 // GetTouchStartListeners returns the "touch-start" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetTouchStartListeners(view View, subviewID ...string) []func(View, TouchEvent) {
-	return getOneArgEventListeners[View, TouchEvent](view, subviewID, TouchStart)
+//
+// Result elements can be of the following types:
+//   - func(rui.View, rui.TouchEvent),
+//   - func(rui.View),
+//   - func(rui.TouchEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetTouchStartListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, TouchEvent](view, subviewID, TouchStart)
 }
 
 // GetTouchEndListeners returns the "touch-end" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetTouchEndListeners(view View, subviewID ...string) []func(View, TouchEvent) {
-	return getOneArgEventListeners[View, TouchEvent](view, subviewID, TouchEnd)
+//
+// Result elements can be of the following types:
+//   - func(rui.View, rui.TouchEvent),
+//   - func(rui.View),
+//   - func(rui.TouchEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetTouchEndListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, TouchEvent](view, subviewID, TouchEnd)
 }
 
 // GetTouchMoveListeners returns the "touch-move" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetTouchMoveListeners(view View, subviewID ...string) []func(View, TouchEvent) {
-	return getOneArgEventListeners[View, TouchEvent](view, subviewID, TouchMove)
+//
+// Result elements can be of the following types:
+//   - func(rui.View, rui.TouchEvent),
+//   - func(rui.View),
+//   - func(rui.TouchEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetTouchMoveListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, TouchEvent](view, subviewID, TouchMove)
 }
 
 // GetTouchCancelListeners returns the "touch-cancel" listener list. If there are no listeners then the empty list is returned.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
-func GetTouchCancelListeners(view View, subviewID ...string) []func(View, TouchEvent) {
-	return getOneArgEventListeners[View, TouchEvent](view, subviewID, TouchCancel)
+//
+// Result elements can be of the following types:
+//   - func(rui.View, rui.TouchEvent),
+//   - func(rui.View),
+//   - func(rui.TouchEvent),
+//   - func(),
+//   - string.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
+func GetTouchCancelListeners(view View, subviewID ...string) []any {
+	return getOneArgEventRawListeners[View, TouchEvent](view, subviewID, TouchCancel)
 }

transform.go

@@ -398,7 +398,10 @@ func valueToTransformProperty(value any) TransformProperty {
 		}
 
 	case string:
-		if obj := ParseDataText(value); obj != nil {
+		obj, err := ParseDataText(value)
+		if err != nil {
+			ErrorLog(err.Error())
+		} else {
 			return parseObject(obj)
 		}
 	}
@@ -647,7 +650,9 @@ func transformOriginCSS(x, y, z SizeUnit, session Session) string {
 
 // GetTransform returns a view transform:  translation, scale and rotation over x, y and z axes as well as a distortion of a view along x and y axes.
 // The default value is nil (no transform)
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTransform(view View, subviewID ...string) TransformProperty {
 	return transformStyledProperty(view, subviewID, Transform)
 }
@@ -655,14 +660,18 @@ func GetTransform(view View, subviewID ...string) TransformProperty {
 // GetPerspective returns a distance between the z = 0 plane and the user in order to give a 3D-positioned
 // element some perspective. Each 3D element with z > 0 becomes larger; each 3D-element with z < 0 becomes smaller.
 // The default value is 0 (no 3D effects).
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetPerspective(view View, subviewID ...string) SizeUnit {
 	return sizeStyledProperty(view, subviewID, Perspective, false)
 }
 
 // GetPerspectiveOrigin returns a x- and y-coordinate of the position at which the viewer is looking.
 // It is used as the vanishing point by the Perspective property. The default value is (50%, 50%).
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetPerspectiveOrigin(view View, subviewID ...string) (SizeUnit, SizeUnit) {
 	view = getSubview(view, subviewID)
 	if view == nil {
@@ -675,14 +684,18 @@ func GetPerspectiveOrigin(view View, subviewID ...string) (SizeUnit, SizeUnit) {
 // visible when turned towards the user. Values:
 // true - the back face is visible when turned towards the user (default value).
 // false - the back face is hidden, effectively making the element invisible when turned away from the user.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetBackfaceVisible(view View, subviewID ...string) bool {
 	return boolStyledProperty(view, subviewID, BackfaceVisible, false)
 }
 
 // GetTransformOrigin returns a x-, y-, and z-coordinate of the point around which a view transformation is applied.
 // The default value is (50%, 50%, 50%).
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTransformOrigin(view View, subviewID ...string) (SizeUnit, SizeUnit, SizeUnit) {
 	view = getSubview(view, subviewID)
 	if view == nil {
@@ -692,7 +705,9 @@ func GetTransformOrigin(view View, subviewID ...string) (SizeUnit, SizeUnit, Siz
 }
 
 // GetTranslate returns a x-, y-, and z-axis translation value of a 2D/3D translation
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTranslate(view View, subviewID ...string) (SizeUnit, SizeUnit, SizeUnit) {
 	if transform := GetTransform(view, subviewID...); transform != nil {
 		return transform.getTranslate(view.Session())
@@ -702,7 +717,9 @@ func GetTranslate(view View, subviewID ...string) (SizeUnit, SizeUnit, SizeUnit)
 
 // GetSkew returns a angles to use to distort the element along the abscissa (x-axis)
 // and the ordinate (y-axis). The default value is 0.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetSkew(view View, subviewID ...string) (AngleUnit, AngleUnit) {
 	if transform := GetTransform(view, subviewID...); transform != nil {
 		x, y, _ := transform.getSkew(view.Session())
@@ -712,7 +729,9 @@ func GetSkew(view View, subviewID ...string) (AngleUnit, AngleUnit) {
 }
 
 // GetScale returns a x-, y-, and z-axis scaling value of a 2D/3D scale. The default value is 1.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetScale(view View, subviewID ...string) (float64, float64, float64) {
 	if transform := GetTransform(view, subviewID...); transform != nil {
 		session := view.Session()
@@ -725,7 +744,9 @@ func GetScale(view View, subviewID ...string) (float64, float64, float64) {
 }
 
 // GetRotate returns a x-, y, z-coordinate of the vector denoting the axis of rotation, and the angle of the view rotation
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetRotate(view View, subviewID ...string) (float64, float64, float64, AngleUnit) {
 	if transform := GetTransform(view, subviewID...); transform != nil {
 		session := view.Session()

view.go

@@ -30,6 +30,8 @@ func (frame Frame) Bottom() float64 {
 	return frame.Top + frame.Height
 }
 
+const changeListeners PropertyName = "change-listeners"
+
 // View represents a base view interface
 type View interface {
 	ViewStyle
@@ -66,8 +68,18 @@ type View interface {
 	// a description of the error is written to the log
 	SetAnimated(tag PropertyName, value any, animation AnimationProperty) bool
 
-	// SetChangeListener set the function to track the change of the View property
-	SetChangeListener(tag PropertyName, listener func(View, PropertyName))
+	// SetChangeListener set the function (the second argument) to track the change of the View property (the first argument).
+	//
+	// Allowed listener function formats:
+	//
+	//  func(view rui.View, property rui.PropertyName)
+	//  func(view rui.View)
+	//  func(property rui.PropertyName)
+	//  func()
+	//  string
+	//
+	// If the second argument is given as a string, it specifies the name of the binding function.
+	SetChangeListener(tag PropertyName, listener any) bool
 
 	// HasFocus returns 'true' if the view has focus
 	HasFocus() bool
@@ -90,8 +102,9 @@ type View interface {
 	htmlProperties(self View, buffer *strings.Builder)
 	cssStyle(self View, builder cssBuilder)
 	addToCSSStyle(addCSS map[string]string)
-	exscludeTags() []PropertyName
+	excludeTags() []PropertyName
 	htmlDisabledProperty() bool
+	binding() any
 
 	onResize(self View, x, y, width, height float64)
 	onItemResize(self View, index string, x, y, width, height float64)
@@ -109,7 +122,7 @@ type viewData struct {
 	_htmlID          string
 	parentID         string
 	systemClass      string
-	changeListener   map[PropertyName]func(View, PropertyName)
+	changeListener   map[PropertyName]oneArgListener[View, PropertyName]
 	singleTransition map[PropertyName]AnimationProperty
 	addCSS           map[string]string
 	frame            Frame
@@ -161,7 +174,7 @@ func (view *viewData) init(session Session) {
 	view.changed = view.propertyChanged
 	view.tag = "View"
 	view.session = session
-	view.changeListener = map[PropertyName]func(View, PropertyName){}
+	view.changeListener = map[PropertyName]oneArgListener[View, PropertyName]{}
 	view.addCSS = map[string]string{}
 	//view.animation = map[string]AnimationEndListener{}
 	view.singleTransition = map[PropertyName]AnimationProperty{}
@@ -195,6 +208,18 @@ func (view *viewData) ID() string {
 	return view.viewID
 }
 
+func (view *viewData) binding() any {
+	if result := view.getRaw(Binding); result != nil {
+		return result
+	}
+
+	if parent := view.Parent(); parent != nil {
+		return parent.binding()
+	}
+
+	return nil
+}
+
 func (view *viewData) ViewByID(id string) View {
 	if id == view.ID() {
 		if v := view.session.viewByHTMLID(view.htmlID()); v != nil {
@@ -229,11 +254,8 @@ func (view *viewData) Remove(tag PropertyName) {
 	if view.created && len(changedTags) > 0 {
 		for _, tag := range changedTags {
 			view.changed(tag)
-		}
-
-		for _, tag := range changedTags {
 			if listener, ok := view.changeListener[tag]; ok {
-				listener(view, tag)
+				listener.Run(view, tag)
 			}
 		}
 	}
@@ -260,11 +282,8 @@ func (view *viewData) Set(tag PropertyName, value any) bool {
 	if view.created && len(changedTags) > 0 {
 		for _, tag := range changedTags {
 			view.changed(tag)
-		}
-
-		for _, tag := range changedTags {
 			if listener, ok := view.changeListener[tag]; ok {
-				listener(view, tag)
+				listener.Run(view, tag)
 			}
 		}
 	}
@@ -282,7 +301,8 @@ func normalizeViewTag(tag PropertyName) PropertyName {
 }
 
 func (view *viewData) getFunc(tag PropertyName) any {
-	if tag == ID {
+	switch tag {
+	case ID:
 		if id := view.ID(); id != "" {
 			return id
 		} else {
@@ -304,6 +324,14 @@ func (view *viewData) removeFunc(tag PropertyName) []PropertyName {
 			changedTags = []PropertyName{}
 		}
 
+	case Binding:
+		if view.getRaw(Binding) != nil {
+			view.setRaw(Binding, nil)
+			changedTags = []PropertyName{Binding}
+		} else {
+			changedTags = []PropertyName{}
+		}
+
 	case Animation:
 		if val := view.getRaw(Animation); val != nil {
 			if animations, ok := val.([]AnimationProperty); ok {
@@ -336,6 +364,33 @@ func (view *viewData) setFunc(tag PropertyName, value any) []PropertyName {
 		notCompatibleType(ID, value)
 		return nil
 
+	case Binding:
+		view.setRaw(Binding, value)
+		return []PropertyName{Binding}
+
+	case changeListeners:
+		switch value := value.(type) {
+		case DataObject:
+			for i := range value.PropertyCount() {
+				node := value.Property(i)
+				if node.Type() == TextNode {
+					if text := node.Text(); text != "" {
+						view.changeListener[PropertyName(node.Tag())] = newOneArgListenerBinding[View, PropertyName](text)
+					}
+				}
+			}
+			if len(view.changeListener) > 0 {
+				view.setRaw(changeListeners, view.changeListener)
+			}
+			return []PropertyName{tag}
+
+		case DataNode:
+			if value.Type() == ObjectNode {
+				return view.setFunc(tag, value.Object())
+			}
+		}
+		return []PropertyName{}
+
 	case Animation:
 		oldAnimations := []AnimationProperty{}
 		if val := view.getRaw(Animation); val != nil {
@@ -386,20 +441,15 @@ func (view *viewData) setFunc(tag PropertyName, value any) []PropertyName {
 	case TransitionRunEvent, TransitionStartEvent, TransitionEndEvent, TransitionCancelEvent:
 		result := setOneArgEventListener[View, PropertyName](view, tag, value)
 		if result == nil {
-			result = setOneArgEventListener[View, string](view, tag, value)
-			if result != nil {
-				if listeners, ok := view.getRaw(tag).([]func(View, string)); ok {
-					newListeners := make([]func(View, PropertyName), len(listeners))
-					for i, listener := range listeners {
-						newListeners[i] = func(view View, name PropertyName) {
-							listener(view, string(name))
-						}
-					}
-					view.setRaw(tag, newListeners)
-					return result
+			if listeners, ok := valueToOneArgEventListeners[View, string](view); ok && len(listeners) > 0 {
+				newListeners := make([]oneArgListener[View, PropertyName], len(listeners))
+				for i, listener := range listeners {
+					newListeners[i] = newOneArgListenerVE(func(view View, name PropertyName) {
+						listener.Run(view, string(name))
+					})
 				}
-				view.setRaw(tag, nil)
-				return nil
+				view.setRaw(tag, newListeners)
+				result = []PropertyName{tag}
 			}
 		}
 		return result
@@ -909,7 +959,7 @@ func (view *viewData) propertyChanged(tag PropertyName) {
 	case DropEffectAllowed:
 		effect := GetDropEffectAllowed(view)
 		if effect >= DropEffectCopy && effect >= DropEffectAll {
-			values := []string{"undifined", "copy", "move", "copyMove", "link", "copyLink", "linkMove", "all"}
+			values := []string{"undefined", "copy", "move", "copyMove", "link", "copyLink", "linkMove", "all"}
 			session.updateProperty(htmlID, "data-drop-effect-allowed", values[effect])
 		} else {
 			session.removeProperty(htmlID, "data-drop-effect-allowed")
@@ -1016,8 +1066,8 @@ func (view *viewData) htmlProperties(self View, buffer *strings.Builder) {
 	}
 
 	if view.frame.Left != 0 || view.frame.Top != 0 || view.frame.Width != 0 || view.frame.Height != 0 {
-		buffer.WriteString(fmt.Sprintf(` data-left="%g" data-top="%g" data-width="%g" data-height="%g"`,
-			view.frame.Left, view.frame.Top, view.frame.Width, view.frame.Height))
+		fmt.Fprintf(buffer, ` data-left="%g" data-top="%g" data-width="%g" data-height="%g"`,
+			view.frame.Left, view.frame.Top, view.frame.Width, view.frame.Height)
 	}
 }
 
@@ -1142,13 +1192,13 @@ func (view *viewData) handleCommand(self View, command PropertyName, data DataOb
 	case FocusEvent:
 		view.hasFocus = true
 		for _, listener := range getNoArgEventListeners[View](view, nil, command) {
-			listener(self)
+			listener.Run(self)
 		}
 
 	case LostFocusEvent:
 		view.hasFocus = false
 		for _, listener := range getNoArgEventListeners[View](view, nil, command) {
-			listener(self)
+			listener.Run(self)
 		}
 
 	case TransitionRunEvent, TransitionStartEvent, TransitionEndEvent, TransitionCancelEvent:
@@ -1231,12 +1281,33 @@ func (view *viewData) handleCommand(self View, command PropertyName, data DataOb
 
 }
 
-func (view *viewData) SetChangeListener(tag PropertyName, listener func(View, PropertyName)) {
+func (view *viewData) SetChangeListener(tag PropertyName, listener any) bool {
 	if listener == nil {
 		delete(view.changeListener, tag)
 	} else {
-		view.changeListener[tag] = listener
+		switch listener := listener.(type) {
+		case func():
+			view.changeListener[tag] = newOneArgListener0[View, PropertyName](listener)
+
+		case func(View):
+			view.changeListener[tag] = newOneArgListenerV[View, PropertyName](listener)
+
+		case func(PropertyName):
+			view.changeListener[tag] = newOneArgListenerE[View](listener)
+
+		case func(View, PropertyName):
+			view.changeListener[tag] = newOneArgListenerVE(listener)
+
+		case string:
+			view.changeListener[tag] = newOneArgListenerBinding[View, PropertyName](listener)
+
+		default:
+			return false
+		}
+
+		view.setRaw(changeListeners, view.changeListener)
 	}
+	return true
 }
 
 func (view *viewData) HasFocus() bool {
@@ -1250,6 +1321,6 @@ func (view *viewData) String() string {
 	return buffer.String()
 }
 
-func (view *viewData) exscludeTags() []PropertyName {
+func (view *viewData) excludeTags() []PropertyName {
 	return nil
 }

viewFactory.go

@@ -6,7 +6,7 @@ import (
 	"strings"
 )
 
-var viewCreators = map[string]func(Session) View{
+var systemViewCreators = map[string]func(Session) View{
 	"View":           newView,
 	"ColumnLayout":   newColumnLayout,
 	"ListLayout":     newListLayout,
@@ -36,84 +36,117 @@ var viewCreators = map[string]func(Session) View{
 	"VideoPlayer":    newVideoPlayer,
 }
 
+// ViewCreateListener is the listener interface of a view create event
+type ViewCreateListener interface {
+	// OnCreate is a function of binding object that is called by the CreateViewFromText, CreateViewFromResources,
+	// and CreateViewFromObject functions after the creation of a view
+	OnCreate(view View)
+}
+
+var viewCreate map[string]func(Session) View = nil
+
+func viewCreators() map[string]func(Session) View {
+	if viewCreate == nil {
+		viewCreate = map[string]func(Session) View{}
+		for tag, fn := range systemViewCreators {
+			viewCreate[strings.ToLower(tag)] = fn
+		}
+	}
+	return viewCreate
+}
+
 // RegisterViewCreator register function of creating view
 func RegisterViewCreator(tag string, creator func(Session) View) bool {
-	builtinViews := []string{
-		"View",
-		"ViewsContainer",
-		"ColumnLayout",
-		"ListLayout",
-		"GridLayout",
-		"StackLayout",
-		"TabsLayout",
-		"AbsoluteLayout",
-		"Resizable",
-		"DetailsView",
-		"TextView",
-		"Button",
-		"Checkbox",
-		"DropDownList",
-		"ProgressBar",
-		"NumberPicker",
-		"ColorPicker",
-		"DatePicker",
-		"TimePicker",
-		"EditView",
-		"ListView",
-		"CanvasView",
-		"ImageView",
-		"TableView",
-	}
-
-	for _, name := range builtinViews {
-		if name == tag {
+	loTag := strings.ToLower(tag)
+	for name := range systemViewCreators {
+		if name == loTag {
+			ErrorLog(`It is forbidden to override the function of ` + tag + ` creating`)
 			return false
 		}
 	}
 
-	viewCreators[tag] = creator
+	viewCreators()[loTag] = creator
 	return true
 }
 
-// CreateViewFromObject create new View and initialize it by Node data
-func CreateViewFromObject(session Session, object DataObject) View {
-	tag := object.Tag()
-
-	if creator, ok := viewCreators[tag]; ok {
-		if !session.ignoreViewUpdates() {
-			session.setIgnoreViewUpdates(true)
-			defer session.setIgnoreViewUpdates(false)
-		}
-		view := creator(session)
-		view.init(session)
-		if customView, ok := view.(CustomView); ok {
-			if !InitCustomView(customView, tag, session, nil) {
-				return nil
-			}
-		}
-		parseProperties(view, object)
-		return view
+// CreateViewFromObject create new View and initialize it by DataObject data. Parameters:
+//   - session - the session to which the view will be attached (should not be nil);
+//   - object - data describing View;
+//   - binding - object assigned to the Binding property (may be nil).
+//
+// If the function fails, it returns nil and an error message is written to the log.
+func CreateViewFromObject(session Session, object DataObject, binding any) View {
+	if session == nil {
+		ErrorLog(`Session must not be nil`)
+		return nil
 	}
 
-	ErrorLog(`Unknown view type "` + object.Tag() + `"`)
-	return nil
+	tag := object.Tag()
+	creator, ok := viewCreators()[strings.ToLower(tag)]
+	if !ok {
+		ErrorLog(`Unknown view type "` + tag + `"`)
+		return nil
+	}
+
+	if !session.ignoreViewUpdates() {
+		session.setIgnoreViewUpdates(true)
+		defer session.setIgnoreViewUpdates(false)
+	}
+
+	view := creator(session)
+	view.init(session)
+	if customView, ok := view.(CustomView); ok {
+		if !InitCustomView(customView, tag, session, nil) {
+			return nil
+		}
+	}
+	parseProperties(view, object)
+	if binding != nil {
+		view.setRaw(Binding, binding)
+		if listener, ok := binding.(ViewCreateListener); ok {
+			listener.OnCreate(view)
+		}
+	}
+	return view
 }
 
-// CreateViewFromText create new View and initialize it by content of text
-func CreateViewFromText(session Session, text string) View {
-	if data := ParseDataText(text); data != nil {
-		return CreateViewFromObject(session, data)
+// CreateViewFromText create new View and initialize it by content of text. Parameters:
+//   - session - the session to which the view will be attached (should not be nil);
+//   - text - text describing View;
+//   - binding - object assigned to the Binding property (optional parameter).
+//
+// If the function fails, it returns nil and an error message is written to the log.
+func CreateViewFromText(session Session, text string, binding ...any) View {
+	data, err := ParseDataText(text)
+	if err != nil {
+		ErrorLog(err.Error())
+		return nil
 	}
-	return nil
+
+	var b any = nil
+	if len(binding) > 0 {
+		b = binding[0]
+	}
+	return CreateViewFromObject(session, data, b)
 }
 
 // CreateViewFromResources create new View and initialize it by the content of
-// the resource file from "views" directory
-func CreateViewFromResources(session Session, name string) View {
+// the resource file from "views" directory. Parameters:
+//   - session - the session to which the view will be attached (should not be nil);
+//   - name - file name in the views folder of the application resources (it is not necessary to specify the .rui extension, it is added automatically);
+//   - binding - object assigned to the Binding property (optional parameter).
+//
+// If the function fails, it returns nil and an error message is written to the log.
+func CreateViewFromResources(session Session, name string, binding ...any) View {
 	if strings.ToLower(filepath.Ext(name)) != ".rui" {
 		name += ".rui"
 	}
 
+	var b any = nil
+	if len(binding) > 0 {
+		b = binding[0]
+	}
+
 	for _, fs := range resources.embedFS {
 		rootDirs := resources.embedRootDirs(fs)
 		for _, dir := range rootDirs {
@@ -123,15 +156,21 @@ func CreateViewFromResources(session Session, name string) View {
 
 			case viewDir:
 				if data, err := fs.ReadFile(dir + "/" + name); err == nil {
-					if data := ParseDataText(string(data)); data != nil {
-						return CreateViewFromObject(session, data)
+					data, err := ParseDataText(string(data))
+					if err != nil {
+						ErrorLog(err.Error())
+					} else {
+						return CreateViewFromObject(session, data, b)
 					}
 				}
 
 			default:
 				if data, err := fs.ReadFile(dir + "/" + viewDir + "/" + name); err == nil {
-					if data := ParseDataText(string(data)); data != nil {
-						return CreateViewFromObject(session, data)
+					data, err := ParseDataText(string(data))
+					if err != nil {
+						ErrorLog(err.Error())
+					} else {
+						return CreateViewFromObject(session, data, b)
 					}
 				}
 			}
@@ -140,8 +179,11 @@ func CreateViewFromResources(session Session, name string) View {
 
 	if resources.path != "" {
 		if data, err := os.ReadFile(resources.path + viewDir + "/" + name); err == nil {
-			if data := ParseDataText(string(data)); data != nil {
-				return CreateViewFromObject(session, data)
+			data, err := ParseDataText(string(data))
+			if err != nil {
+				ErrorLog(err.Error())
+			} else {
+				return CreateViewFromObject(session, data, b)
 			}
 		}
 	}

viewStyle.go

@@ -2,9 +2,10 @@ package rui
 
 import (
 	"fmt"
-	"sort"
+	"slices"
 	"strconv"
 	"strings"
+	"time"
 )
 
 // ViewStyle interface of the style of view
@@ -551,26 +552,126 @@ func viewStyleGet(style Properties, tag PropertyName) any {
 }
 
 func supportedPropertyValue(value any) bool {
-	switch value.(type) {
-	case string:
+	switch value := value.(type) {
+	case string, bool, float32, float64, int, stringWriter, fmt.Stringer:
+		return true
+
 	case []string:
-	case bool:
-	case float32:
-	case float64:
-	case int:
-	case stringWriter:
-	case fmt.Stringer:
+		return len(value) > 0
+
 	case []ShadowProperty:
+		return len(value) > 0
+
 	case []View:
+		return len(value) > 0
+
 	case []any:
+		return len(value) > 0
+
 	case []BackgroundElement:
+		return len(value) > 0
+
 	case []BackgroundGradientPoint:
+		return len(value) > 0
+
 	case []BackgroundGradientAngle:
+		return len(value) > 0
+
 	case map[PropertyName]AnimationProperty:
+		return len(value) > 0
+
+	case []noArgListener[View]:
+		return getNoArgBinding(value) != ""
+
+	case []noArgListener[ImageView]:
+		return getNoArgBinding(value) != ""
+
+	case []noArgListener[MediaPlayer]:
+		return getNoArgBinding(value) != ""
+
+	case []oneArgListener[View, KeyEvent]:
+		return getOneArgBinding(value) != ""
+
+	case []oneArgListener[View, MouseEvent]:
+		return getOneArgBinding(value) != ""
+
+	case []oneArgListener[View, TouchEvent]:
+		return getOneArgBinding(value) != ""
+
+	case []oneArgListener[View, PointerEvent]:
+		return getOneArgBinding(value) != ""
+
+	case []oneArgListener[View, PropertyName]:
+		return getOneArgBinding(value) != ""
+
+	case []oneArgListener[View, string]:
+		return getOneArgBinding(value) != ""
+
+	case []oneArgListener[View, Frame]:
+		return getOneArgBinding(value) != ""
+
+	case []oneArgListener[View, DragAndDropEvent]:
+		return getOneArgBinding(value) != ""
+
+	case []oneArgListener[Checkbox, bool]:
+		return getOneArgBinding(value) != ""
+
+	case []oneArgListener[FilePicker, []FileInfo]:
+		return getOneArgBinding(value) != ""
+
+	case []oneArgListener[ListView, int]:
+		return getOneArgBinding(value) != ""
+
+	case []oneArgListener[ListView, []int]:
+		return getOneArgBinding(value) != ""
+
+	case []oneArgListener[MediaPlayer, float64]:
+		return getOneArgBinding(value) != ""
+
+	case []oneArgListener[TableView, int]:
+		return getOneArgBinding(value) != ""
+
+	case []oneArgListener[TabsLayout, int]:
+		return getOneArgBinding(value) != ""
+
+	case []twoArgListener[ColorPicker, Color]:
+		return getTwoArgBinding(value) != ""
+
+	case []twoArgListener[DatePicker, time.Time]:
+		return getTwoArgBinding(value) != ""
+
+	case []twoArgListener[TimePicker, time.Time]:
+		return getTwoArgBinding(value) != ""
+
+	case []twoArgListener[DropDownList, int]:
+		return getTwoArgBinding(value) != ""
+
+	case []twoArgListener[EditView, string]:
+		return getTwoArgBinding(value) != ""
+
+	case []twoArgListener[NumberPicker, float64]:
+		return getTwoArgBinding(value) != ""
+
+	case []twoArgListener[TableView, int]:
+		return getTwoArgBinding(value) != ""
+
+	case []twoArgListener[TabsLayout, int]:
+		return getTwoArgBinding(value) != ""
+
+	case []mediaPlayerErrorListener:
+		return getMediaPlayerErrorListenerBinding(value) != ""
+
+	case map[PropertyName]oneArgListener[View, PropertyName]:
+		for _, listener := range value {
+			if text, ok := listener.rawListener().(string); ok && text != "" {
+				return true
+			}
+		}
+		return false
+
 	default:
 		return false
 	}
-	return true
 }
 
 func writePropertyValue(buffer *strings.Builder, tag PropertyName, value any, indent string) {
@@ -640,8 +741,8 @@ func writePropertyValue(buffer *strings.Builder, tag PropertyName, value any, in
 					writeString(text)
 					buffer.WriteString(",\n")
 				}
+				buffer.WriteString(indent)
 			}
-			buffer.WriteString(indent)
 			buffer.WriteRune(']')
 		}
 
@@ -653,10 +754,10 @@ func writePropertyValue(buffer *strings.Builder, tag PropertyName, value any, in
 		}
 
 	case float32:
-		buffer.WriteString(fmt.Sprintf("%g", float64(value)))
+		fmt.Fprintf(buffer, "%g", float64(value))
 
 	case float64:
-		buffer.WriteString(fmt.Sprintf("%g", value))
+		fmt.Fprintf(buffer, "%g", value)
 
 	case int:
 		if prop, ok := enumProperties[tag]; ok && value >= 0 && value < len(prop.values) {
@@ -698,14 +799,14 @@ func writePropertyValue(buffer *strings.Builder, tag PropertyName, value any, in
 			buffer.WriteString("[]")
 
 		case 1:
-			writeViewStyle(value[0].Tag(), value[0], buffer, indent, value[0].exscludeTags())
+			writeViewStyle(value[0].Tag(), value[0], buffer, indent, value[0].excludeTags())
 
 		default:
 			buffer.WriteString("[\n")
 			indent2 := indent + "\t"
 			for _, v := range value {
 				buffer.WriteString(indent2)
-				writeViewStyle(v.Tag(), v, buffer, indent2, v.exscludeTags())
+				writeViewStyle(v.Tag(), v, buffer, indent2, v.excludeTags())
 				buffer.WriteString(",\n")
 			}
 
@@ -791,9 +892,7 @@ func writePropertyValue(buffer *strings.Builder, tag PropertyName, value any, in
 			for tag := range value {
 				tags = append(tags, tag)
 			}
-			sort.Slice(tags, func(i, j int) bool {
-				return tags[i] < tags[j]
-			})
+			slices.Sort(tags)
 			buffer.WriteString("[\n")
 			indent2 := indent + "\t"
 			for _, tag := range tags {
@@ -806,6 +905,104 @@ func writePropertyValue(buffer *strings.Builder, tag PropertyName, value any, in
 			buffer.WriteString(indent)
 			buffer.WriteRune(']')
 		}
+
+	case []noArgListener[View]:
+		buffer.WriteString(getNoArgBinding(value))
+
+	case []noArgListener[ImageView]:
+		buffer.WriteString(getNoArgBinding(value))
+
+	case []noArgListener[MediaPlayer]:
+		buffer.WriteString(getNoArgBinding(value))
+
+	case []oneArgListener[View, KeyEvent]:
+		buffer.WriteString(getOneArgBinding(value))
+
+	case []oneArgListener[View, MouseEvent]:
+		buffer.WriteString(getOneArgBinding(value))
+
+	case []oneArgListener[View, TouchEvent]:
+		buffer.WriteString(getOneArgBinding(value))
+
+	case []oneArgListener[View, PointerEvent]:
+		buffer.WriteString(getOneArgBinding(value))
+
+	case []oneArgListener[View, PropertyName]:
+		buffer.WriteString(getOneArgBinding(value))
+
+	case []oneArgListener[View, string]:
+		buffer.WriteString(getOneArgBinding(value))
+
+	case []oneArgListener[View, Frame]:
+		buffer.WriteString(getOneArgBinding(value))
+
+	case []oneArgListener[View, DragAndDropEvent]:
+		buffer.WriteString(getOneArgBinding(value))
+
+	case []oneArgListener[Checkbox, bool]:
+		buffer.WriteString(getOneArgBinding(value))
+
+	case []oneArgListener[FilePicker, []FileInfo]:
+		buffer.WriteString(getOneArgBinding(value))
+
+	case []oneArgListener[ListView, int]:
+		buffer.WriteString(getOneArgBinding(value))
+
+	case []oneArgListener[ListView, []int]:
+		buffer.WriteString(getOneArgBinding(value))
+
+	case []oneArgListener[MediaPlayer, float64]:
+		buffer.WriteString(getOneArgBinding(value))
+
+	case []oneArgListener[TableView, int]:
+		buffer.WriteString(getOneArgBinding(value))
+
+	case []oneArgListener[TabsLayout, int]:
+		buffer.WriteString(getOneArgBinding(value))
+
+	case []twoArgListener[ColorPicker, Color]:
+		buffer.WriteString(getTwoArgBinding(value))
+
+	case []twoArgListener[DatePicker, time.Time]:
+		buffer.WriteString(getTwoArgBinding(value))
+
+	case []twoArgListener[TimePicker, time.Time]:
+		buffer.WriteString(getTwoArgBinding(value))
+
+	case []twoArgListener[DropDownList, int]:
+		buffer.WriteString(getTwoArgBinding(value))
+
+	case []twoArgListener[EditView, string]:
+		buffer.WriteString(getTwoArgBinding(value))
+
+	case []twoArgListener[NumberPicker, float64]:
+		buffer.WriteString(getTwoArgBinding(value))
+
+	case []twoArgListener[TableView, int]:
+		buffer.WriteString(getTwoArgBinding(value))
+
+	case []twoArgListener[TabsLayout, int]:
+		buffer.WriteString(getTwoArgBinding(value))
+
+	case []mediaPlayerErrorListener:
+		buffer.WriteString(getMediaPlayerErrorListenerBinding(value))
+
+	case map[PropertyName]oneArgListener[View, PropertyName]:
+		buffer.WriteString("_{")
+		for key, listener := range value {
+			if text, ok := listener.rawListener().(string); ok && text != "" {
+				buffer.WriteRune('\n')
+				buffer.WriteString(indent)
+				buffer.WriteRune('\t')
+				writeString(string(key))
+				buffer.WriteString(" = ")
+				writeString(text)
+				buffer.WriteRune(',')
+			}
+			buffer.WriteRune('\n')
+			buffer.WriteString(indent)
+			buffer.WriteRune('}')
+		}
 	}
 }
 
@@ -815,19 +1012,15 @@ func writeViewStyle(name string, view Properties, buffer *strings.Builder, inden
 	indent += "\t"
 
 	writeProperty := func(tag PropertyName, value any) {
-		for _, exclude := range excludeTags {
-			if exclude == tag {
-				return
+		if !slices.Contains(excludeTags, tag) {
+			if supportedPropertyValue(value) {
+				buffer.WriteString(indent)
+				buffer.WriteString(string(tag))
+				buffer.WriteString(" = ")
+				writePropertyValue(buffer, tag, value, indent)
+				buffer.WriteString(",\n")
 			}
 		}
-
-		if supportedPropertyValue(value) {
-			buffer.WriteString(indent)
-			buffer.WriteString(string(tag))
-			buffer.WriteString(" = ")
-			writePropertyValue(buffer, tag, value, indent)
-			buffer.WriteString(",\n")
-		}
 	}
 
 	tags := view.AllTags()

viewUtils.go

@@ -355,31 +355,41 @@ func GetTextShadows(view View, subviewID ...string) []ShadowProperty {
 }
 
 // GetBackgroundColor returns a background color of the subview.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetBackgroundColor(view View, subviewID ...string) Color {
 	return colorStyledProperty(view, subviewID, BackgroundColor, false)
 }
 
 // GetAccentColor returns the accent color for UI controls generated by some elements.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetAccentColor(view View, subviewID ...string) Color {
 	return colorStyledProperty(view, subviewID, AccentColor, false)
 }
 
 // GetFontName returns the subview font.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetFontName(view View, subviewID ...string) string {
 	return stringStyledProperty(view, nil, FontName, true)
 }
 
 // GetTextColor returns a text color of the subview.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTextColor(view View, subviewID ...string) Color {
 	return colorStyledProperty(view, subviewID, TextColor, true)
 }
 
 // GetTextSize returns a text size of the subview.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTextSize(view View, subviewID ...string) SizeUnit {
 	return sizeStyledProperty(view, subviewID, TextSize, true)
 }
@@ -392,7 +402,9 @@ func GetTabSize(view View, subviewID ...string) int {
 
 // GetTextWeight returns a text weight of the subview. Returns one of next values:
 // 1, 2, 3, 4 (normal text), 5, 6, 7 (bold text), 8 and 9
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTextWeight(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, TextWeight, NormalFont, true)
 }
@@ -401,7 +413,8 @@ func GetTextWeight(view View, subviewID ...string) int {
 //
 //	LeftAlign = 0, RightAlign = 1, CenterAlign = 2, JustifyAlign = 3
 //
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTextAlign(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, TextAlign, LeftAlign, true)
 }
@@ -410,89 +423,116 @@ func GetTextAlign(view View, subviewID ...string) int {
 //
 //	TextWrapOn = 0, TextWrapOff = 1, TextWrapBalance = 3
 //
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTextWrap(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, TextWrap, TextWrapOn, true)
 }
 
 // GetTextIndent returns a text indent of the subview.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTextIndent(view View, subviewID ...string) SizeUnit {
 	return sizeStyledProperty(view, subviewID, TextIndent, true)
 }
 
 // GetLetterSpacing returns a letter spacing of the subview.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetLetterSpacing(view View, subviewID ...string) SizeUnit {
 	return sizeStyledProperty(view, subviewID, LetterSpacing, true)
 }
 
 // GetWordSpacing returns a word spacing of the subview.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetWordSpacing(view View, subviewID ...string) SizeUnit {
 	return sizeStyledProperty(view, subviewID, WordSpacing, true)
 }
 
 // GetLineHeight returns a height of a text line of the subview.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetLineHeight(view View, subviewID ...string) SizeUnit {
 	return sizeStyledProperty(view, subviewID, LineHeight, true)
 }
 
 // IsItalic returns "true" if a text font of the subview is displayed in italics, "false" otherwise.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func IsItalic(view View, subviewID ...string) bool {
 	return boolStyledProperty(view, subviewID, Italic, true)
 }
 
 // IsSmallCaps returns "true" if a text font of the subview is displayed in small caps, "false" otherwise.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func IsSmallCaps(view View, subviewID ...string) bool {
 	return boolStyledProperty(view, subviewID, SmallCaps, true)
 }
 
 // IsStrikethrough returns "true" if a text font of the subview is displayed strikethrough, "false" otherwise.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func IsStrikethrough(view View, subviewID ...string) bool {
 	return boolStyledProperty(view, subviewID, Strikethrough, true)
 }
 
 // IsOverline returns "true" if a text font of the subview is displayed overlined, "false" otherwise.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func IsOverline(view View, subviewID ...string) bool {
 	return boolStyledProperty(view, subviewID, Overline, true)
 }
 
 // IsUnderline returns "true" if a text font of the subview is displayed underlined, "false" otherwise.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func IsUnderline(view View, subviewID ...string) bool {
 	return boolStyledProperty(view, subviewID, Underline, true)
 }
 
 // GetTextLineThickness returns the stroke thickness of the decoration line that
 // is used on text in an element, such as a line-through, underline, or overline.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTextLineThickness(view View, subviewID ...string) SizeUnit {
 	return sizeStyledProperty(view, subviewID, TextLineThickness, true)
 }
 
 // GetTextLineStyle returns the stroke style of the decoration line that
 // is used on text in an element, such as a line-through, underline, or overline.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTextLineStyle(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, TextLineStyle, SolidLine, true)
 }
 
 // GetTextLineColor returns the stroke color of the decoration line that
 // is used on text in an element, such as a line-through, underline, or overline.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTextLineColor(view View, subviewID ...string) Color {
 	return colorStyledProperty(view, subviewID, TextLineColor, true)
 }
 
 // GetTextTransform returns a text transform of the subview. Return one of next values:
 // NoneTextTransform (0), CapitalizeTextTransform (1), LowerCaseTextTransform (2) or UpperCaseTextTransform (3)
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTextTransform(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, TextTransform, NoneTextTransform, true)
 }
@@ -500,14 +540,18 @@ func GetTextTransform(view View, subviewID ...string) int {
 // GetWritingMode returns whether lines of text are laid out horizontally or vertically, as well as
 // the direction in which blocks progress. Valid values are HorizontalTopToBottom (0),
 // HorizontalBottomToTop (1), VerticalRightToLeft (2) and VerticalLeftToRight (3)
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetWritingMode(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, WritingMode, HorizontalTopToBottom, true)
 }
 
 // GetTextDirection - returns a direction of text, table columns, and horizontal overflow.
 // Valid values are SystemTextDirection (0), LeftToRightDirection (1), and RightToLeftDirection (2).
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTextDirection(view View, subviewID ...string) int {
 	if view == nil {
 		return SystemTextDirection
@@ -519,7 +563,9 @@ func GetTextDirection(view View, subviewID ...string) int {
 // GetVerticalTextOrientation returns a orientation of the text characters in a line. It only affects text
 // in vertical mode (when "writing-mode" is "vertical-right-to-left" or "vertical-left-to-right").
 // Valid values are MixedTextOrientation (0), UprightTextOrientation (1), and SidewaysTextOrientation (2).
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetVerticalTextOrientation(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, VerticalTextOrientation, MixedTextOrientation, true)
 }
@@ -761,7 +807,9 @@ func BlurViewByID(viewID string, session Session) {
 }
 
 // GetCurrent returns the index of the selected item (<0 if there is no a selected item) or the current view index (StackLayout, TabsLayout).
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetCurrent(view View, subviewID ...string) int {
 	defaultValue := -1
 	if view = getSubview(view, subviewID); view != nil {
@@ -775,7 +823,9 @@ func GetCurrent(view View, subviewID ...string) int {
 }
 
 // IsUserSelect returns "true" if the user can select text, "false" otherwise.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func IsUserSelect(view View, subviewID ...string) bool {
 	if view = getSubview(view, subviewID); view != nil {
 		value, _ := isUserSelect(view)
@@ -821,7 +871,8 @@ func isUserSelect(view View) (bool, bool) {
 // BlendSoftLight (9), BlendDifference (10), BlendExclusion (11), BlendHue (12),
 // BlendSaturation (13), BlendColor (14), BlendLuminosity (15)
 //
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetMixBlendMode(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, MixBlendMode, BlendNormal, true)
 }
@@ -833,13 +884,16 @@ func GetMixBlendMode(view View, subviewID ...string) int {
 // BlendSoftLight (9), BlendDifference (10), BlendExclusion (11), BlendHue (12),
 // BlendSaturation (13), BlendColor (14), BlendLuminosity (15)
 //
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetBackgroundBlendMode(view View, subviewID ...string) int {
 	return enumStyledProperty(view, subviewID, BackgroundBlendMode, BlendNormal, true)
 }
 
 // GetTooltip returns a tooltip text of the subview.
-// If the second argument (subviewID) is not specified or it is "" then a value from the first argument (view) is returned.
+//
+// The second argument (subviewID) specifies the path to the child element whose value needs to be returned.
+// If it is not specified then a value from the first argument (view) is returned.
 func GetTooltip(view View, subviewID ...string) string {
 	if view = getSubview(view, subviewID); view != nil {
 		if value := view.Get(Tooltip); value != nil {

viewsContainer.go

@@ -85,10 +85,13 @@ func (container *viewsContainerData) Append(view View) {
 
 		viewHTML(view, buffer, "")
 		container.Session().appendToInnerHTML(container.htmlID(), buffer.String())
+		container.contentChanged()
+	}
+}
 
-		if listener, ok := container.changeListener[Content]; ok {
-			listener(container, Content)
-		}
+func (container *viewsContainerData) contentChanged() {
+	if listener, ok := container.changeListener[Content]; ok {
+		listener.Run(container, Content)
 	}
 }
 
@@ -113,9 +116,7 @@ func (container *viewsContainerData) insert(view View, index int) bool {
 func (container *viewsContainerData) Insert(view View, index int) {
 	if container.insert(view, index) && container.created {
 		updateInnerHTML(container.htmlID(), container.Session())
-		if listener, ok := container.changeListener[Content]; ok {
-			listener(container, Content)
-		}
+		container.contentChanged()
 	}
 }
 
@@ -131,11 +132,12 @@ func (container *viewsContainerData) removeView(index int) View {
 	}
 
 	view := container.views[index]
-	if index == 0 {
+	switch index {
+	case 0:
 		container.views = container.views[1:]
-	} else if index == count-1 {
+	case count - 1:
 		container.views = container.views[:index]
-	} else {
+	default:
 		container.views = append(container.views[:index], container.views[index+1:]...)
 	}
 
@@ -148,9 +150,7 @@ func (container *viewsContainerData) RemoveView(index int) View {
 	view := container.removeView(index)
 	if view != nil && container.created {
 		container.Session().callFunc("removeView", view.htmlID())
-		if listener, ok := container.changeListener[Content]; ok {
-			listener(container, Content)
-		}
+		container.contentChanged()
 	}
 	return view
 }
@@ -173,12 +173,9 @@ func (container *viewsContainerData) htmlSubviews(self View, buffer *strings.Bui
 }
 
 func viewFromTextValue(text string, session Session) View {
-	if strings.Contains(text, "{") && strings.Contains(text, "}") {
-		data := ParseDataText(text)
-		if data != nil {
-			if view := CreateViewFromObject(session, data); view != nil {
-				return view
-			}
+	if data, err := ParseDataText(text); err == nil {
+		if view := CreateViewFromObject(session, data, nil); view != nil {
+			return view
 		}
 	}
 	return NewTextView(session, Params{Text: text})
@@ -277,7 +274,7 @@ func (container *viewsContainerData) setContent(value any) bool {
 		container.views = views
 
 	case DataObject:
-		if view := CreateViewFromObject(session, value); view != nil {
+		if view := CreateViewFromObject(session, value, nil); view != nil {
 			container.views = []View{view}
 		} else {
 			return false
@@ -287,7 +284,7 @@ func (container *viewsContainerData) setContent(value any) bool {
 		views := []View{}
 		for _, data := range value {
 			if data.IsObject() {
-				if view := CreateViewFromObject(session, data.Object()); view != nil {
+				if view := CreateViewFromObject(session, data.Object(), nil); view != nil {
 					views = append(views, view)
 				}
 			} else {

webBridge.go

@@ -190,7 +190,7 @@ func (bridge *webBridge) argToString(arg any) (string, bool) {
 		for _, val := range arg {
 			buffer.WriteRune(lead)
 			lead = ','
-			buffer.WriteString(fmt.Sprintf("%g", val))
+			fmt.Fprintf(buffer, "%g", val)
 		}
 		buffer.WriteRune(']')
 		return buffer.String(), true