Added drag-and-drop of files

animation.go

@@ -243,7 +243,7 @@ func parseAnimation(obj DataObject) AnimationProperty {
 	animation := new(animationData)
 	animation.init()
 
-	for i := 0; i < obj.PropertyCount(); i++ {
+	for i := range obj.PropertyCount() {
 		if node := obj.Property(i); node != nil {
 			tag := PropertyName(node.Tag())
 			if node.Type() == TextNode {
@@ -491,7 +491,7 @@ func animationSet(properties Properties, tag PropertyName, value any) []Property
 		case DataNode:
 			parseObject := func(obj DataObject) (AnimatedProperty, bool) {
 				result := AnimatedProperty{}
-				for i := 0; i < obj.PropertyCount(); i++ {
+				for i := range obj.PropertyCount() {
 					if node := obj.Property(i); node.Type() == TextNode {
 						propTag := strings.ToLower(node.Tag())
 						switch propTag {
@@ -1050,7 +1050,7 @@ func setAnimationProperty(properties Properties, tag PropertyName, value any) bo
 	case DataNode:
 		animations := []AnimationProperty{}
 		result := true
-		for i := 0; i < value.ArraySize(); i++ {
+		for i := range value.ArraySize() {
 			if obj := value.ArrayElement(i).Object(); obj != nil {
 				if anim := parseAnimation(obj); anim.hasAnimatedProperty() {
 					animations = append(animations, anim)

app_scripts.js

@@ -1008,10 +1008,8 @@ function setInputValue(elementId, text) {
 	}
 }
 
-function fileSelectedEvent(element) {
-	const files = element.files;
-	if (files) {
-		let message = "fileSelected{session=" + sessionID + ",id=" + element.id + ",files=[";
+function filesTextForMessage(files) {
+	let message = "files=[";
 	for(let i = 0; i < files.length; i++) {
 		if (i > 0) {
 			message += ",";
@@ -1021,7 +1019,15 @@ function fileSelectedEvent(element) {
 			",size=" + files[i].size +
 			",mime-type=\"" + files[i].type + "\"}";
 	}
-		sendMessage(message + "]}");
+	message += "]";
+	return message
+}
+
+function fileSelectedEvent(element) {
+	const files = element.files;
+	if (files) {
+		let message = "fileSelected{session=" + sessionID + ",id=" + element.id + "," + filesTextForMessage(files) + "}";
+		sendMessage(message);
 	}
 }
 
@@ -2162,19 +2168,18 @@ function dragAndDropEvent(element, event, tag) {
 			message += ',data="' + dataText + '"';
 		}
 
-		dataText = ""
-		for (const file of event.dataTransfer.files) {
-			if (dataText != "") {
-				dataText += ";";
-			}
-			dataText += file.name;
-		}
-		if (dataText != "") {
-			message += ',files="' + dataText + '"';
+		const files = event.dataTransfer.files
+		if (files && files.length > 0) {
+			message += "," + filesTextForMessage(files)
+			element["dragFiles"] = files;
+		} else {
+			element["dragFiles"] = null;
 		}
+
 		if (event.dataTransfer.effectAllowed && event.dataTransfer.effectAllowed != "uninitialized") {
 			message += ',effect-allowed="' + event.dataTransfer.effectAllowed + '"';
 		}
+		
 		if (event.dataTransfer.dropEffect) {
 			message += ',drop-effect="' + event.dataTransfer.dropEffect + '"';
 		}
@@ -2251,3 +2256,34 @@ function dropEvent(element, event) {
 	event.preventDefault();
 	dragAndDropEvent(element, event, "drop-event")
 }
+
+function loadDropFile(elementId, name, size) {
+	const element = document.getElementById(elementId);
+	if (element) {
+		const files = element["dragFiles"];
+		if (files) {
+			for(let i = 0; i < files.length; i++) {
+				const file = files[i]
+				if (file.name == name && file.size == size) {
+					const reader = new FileReader();
+					reader.onload = function() { 
+						sendMessage("fileLoaded{session=" + sessionID + ",id=" + element.id + 
+							",name=`" + name + 
+							"`,size=" + size +
+							",last-modified=" + file.lastModified +
+							",mime-type=\"" + file.type + 
+							"\",data=`" + reader.result + "`}");
+					}
+					reader.onerror = function(error) {
+						sendMessage("fileLoadingError{session=" + sessionID + ",id=" + element.id + ",name=\"" + name + "\",size=" + size + ",error=`" + error + "`}");
+					}
+					reader.readAsDataURL(file);
+					return
+				}
+			}
+		}
+		sendMessage("fileLoadingError{session=" + sessionID + ",id=" + element.id + ",name=`" + name + "`,size=" + size + ",error=`File not found`}");
+	} else {
+		sendMessage("fileLoadingError{session=" + sessionID + ",id=" + element.id + ",name=`" + name + "`,size=" + size + ",error=`Invalid View id`}");
+	}
+}

background.go

@@ -67,7 +67,7 @@ func createBackground(obj DataObject) BackgroundElement {
 	}
 
 	count := obj.PropertyCount()
-	for i := 0; i < count; i++ {
+	for i := range count {
 		if node := obj.Property(i); node.Type() == TextNode {
 			if value := node.Text(); value != "" {
 				result.Set(PropertyName(node.Tag()), value)

backgroundRadialGradient.go

@@ -279,7 +279,7 @@ func (gradient *backgroundRadialGradient) cssStyle(session Session) string {
 			}
 			buffer.WriteString("ellipse ")
 			shapeText = ""
-			for i := 0; i < count; i++ {
+			for i := range count {
 				buffer.WriteString(value[i].cssString("50%", session))
 				buffer.WriteString(" ")
 			}
@@ -291,7 +291,7 @@ func (gradient *backgroundRadialGradient) cssStyle(session Session) string {
 			}
 			buffer.WriteString("ellipse ")
 			shapeText = ""
-			for i := 0; i < count; i++ {
+			for i := range count {
 				if value[i] != nil {
 					switch value := value[i].(type) {
 					case SizeUnit:

border.go

@@ -433,7 +433,7 @@ func (border *borderProperty) String() string {
 
 func (border *borderProperty) setBorderObject(obj DataObject) bool {
 	result := true
-	for i := 0; i < obj.PropertyCount(); i++ {
+	for i := range obj.PropertyCount() {
 		if node := obj.Property(i); node != nil {
 			tag := PropertyName(node.Tag())
 			switch node.Type() {

customView.go

@@ -346,3 +346,9 @@ func (customView *CustomViewData) SetTransition(tag PropertyName, animation Anim
 		customView.superView.SetTransition(tag, animation)
 	}
 }
+
+func (customView *CustomViewData) LoadFile(file FileInfo, result func(FileInfo, []byte)) {
+	if customView.superView != nil {
+		customView.superView.LoadFile(file, result)
+	}
+}

data.go

@@ -222,7 +222,7 @@ func (object *dataObject) ToParams() Params {
 
 		case ArrayNode:
 			array := []any{}
-			for i := 0; i < node.ArraySize(); i++ {
+			for i := range node.ArraySize() {
 				if data := node.ArrayElement(i); data != nil {
 					if data.IsObject() {
 						if obj := data.Object(); obj != nil {
@@ -465,7 +465,7 @@ func ParseDataText(text string) DataObject {
 							return invalidEscape()
 						}
 						x := 0
-						for i := 0; i < 2; i++ {
+						for range 2 {
 							ch := data[n2]
 							if ch >= '0' && ch <= '9' {
 								x = x*16 + int(ch-'0')
@@ -485,7 +485,7 @@ func ParseDataText(text string) DataObject {
 							return invalidEscape()
 						}
 						x := 0
-						for i := 0; i < 4; i++ {
+						for range 4 {
 							ch := data[n2]
 							if ch >= '0' && ch <= '9' {
 								x = x*16 + int(ch-'0')

dragAndDrop.go

@@ -164,7 +164,7 @@ const (
 type DragAndDropEvent struct {
 	MouseEvent
 	Data          map[string]string
-	Files         string
+	Files         []FileInfo
 	Target        View
 	EffectAllowed int
 	DropEffect    int
@@ -216,7 +216,7 @@ func (event *DragAndDropEvent) init(session Session, data DataObject) {
 		}
 	}
 
-	// TODO files
+	event.Files = parseFilesTag(data)
 }
 
 func stringToDropEffect(text string) (int, bool) {
@@ -436,6 +436,13 @@ func dragAndDropHtml(view View, buffer *strings.Builder) {
 	}
 }
 
+func (view *viewData) LoadFile(file FileInfo, result func(FileInfo, []byte)) {
+	if result != nil {
+		view.fileLoader[file.key()] = result
+		view.Session().callFunc("loadDropFile", view.htmlID(), file.Name, file.Size)
+	}
+}
+
 // 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) {

filePicker.go

@@ -1,7 +1,7 @@
 package rui
 
 import (
-	"encoding/base64"
+	"fmt"
 	"strconv"
 	"strings"
 	"time"
@@ -67,6 +67,8 @@ type FileInfo struct {
 
 	// MimeType - the file's MIME type.
 	MimeType string
+
+	data []byte
 }
 
 // FilePicker represents the FilePicker view
@@ -83,10 +85,11 @@ type FilePicker interface {
 type filePickerData struct {
 	viewData
 	files []FileInfo
-	loader map[int]func(FileInfo, []byte)
+	//loader map[int]func(FileInfo, []byte)
 }
 
-func (file *FileInfo) initBy(node DataValue) {
+func dataToFileInfo(node DataValue) FileInfo {
+	var file FileInfo
 	if obj := node.Object(); obj != nil {
 		file.Name, _ = obj.PropertyValue("name")
 		file.MimeType, _ = obj.PropertyValue("mime-type")
@@ -103,6 +106,11 @@ func (file *FileInfo) initBy(node DataValue) {
 			}
 		}
 	}
+	return file
+}
+
+func (file FileInfo) key() string {
+	return fmt.Sprintf("%s:%d", file.Name, int(file.Size))
 }
 
 // NewFilePicker create new FilePicker object and return it
@@ -122,7 +130,7 @@ func (picker *filePickerData) init(session Session) {
 	picker.tag = "FilePicker"
 	picker.hasHtmlDisabled = true
 	picker.files = []FileInfo{}
-	picker.loader = map[int]func(FileInfo, []byte){}
+	//picker.loader = map[int]func(FileInfo, []byte){}
 	picker.set = picker.setFunc
 	picker.changed = picker.propertyChanged
 
@@ -137,17 +145,24 @@ func (picker *filePickerData) Files() []FileInfo {
 }
 
 func (picker *filePickerData) LoadFile(file FileInfo, result func(FileInfo, []byte)) {
-	if result == nil {
-		return
-	}
-
+	if result != nil {
 		for i, info := range picker.files {
 			if info.Name == file.Name && info.Size == file.Size && info.LastModified == file.LastModified {
-			picker.loader[i] = result
+				if info.data != nil {
+					result(info, info.data)
+				} else {
+					picker.fileLoader[info.key()] = func(file FileInfo, data []byte) {
+						picker.files[i].data = data
+						result(file, data)
+					}
 					picker.Session().callFunc("loadSelectedFile", picker.htmlID(), i)
+				}
 				return
 			}
 		}
+
+		picker.viewData.LoadFile(file, result)
+	}
 }
 
 func (picker *filePickerData) setFunc(tag PropertyName, value any) []PropertyName {
@@ -248,65 +263,30 @@ func (picker *filePickerData) htmlProperties(self View, buffer *strings.Builder)
 	}
 }
 
-func (picker *filePickerData) handleCommand(self View, command PropertyName, data DataObject) bool {
-	switch command {
-	case "fileSelected":
+func parseFilesTag(data DataObject) []FileInfo {
 	if node := data.PropertyByTag("files"); node != nil && node.Type() == ArrayNode {
 		count := node.ArraySize()
 		files := make([]FileInfo, count)
-			for i := 0; i < count; i++ {
+		for i := range count {
 			if value := node.ArrayElement(i); value != nil {
-					files[i].initBy(value)
+				files[i] = dataToFileInfo(value)
 			}
 		}
-			picker.files = files
+		return files
+	}
+	return nil
+}
 
+func (picker *filePickerData) handleCommand(self View, command PropertyName, data DataObject) bool {
+	switch command {
+	case "fileSelected":
+		if files := parseFilesTag(data); files != nil {
+			picker.files = files
 			for _, listener := range GetFileSelectedListeners(picker) {
 				listener(picker, files)
 			}
 		}
 		return true
-
-	case "fileLoaded":
-		if index, ok := dataIntProperty(data, "index"); ok {
-			if result, ok := picker.loader[index]; ok {
-				var file FileInfo
-				file.initBy(data)
-
-				var fileData []byte = nil
-				if base64Data, ok := data.PropertyValue("data"); ok {
-					if index := strings.LastIndex(base64Data, ","); index >= 0 {
-						base64Data = base64Data[index+1:]
-					}
-					decode, err := base64.StdEncoding.DecodeString(base64Data)
-					if err == nil {
-						fileData = decode
-					} else {
-						ErrorLog(err.Error())
-					}
-				}
-
-				result(file, fileData)
-				delete(picker.loader, index)
-			}
-		}
-		return true
-
-	case "fileLoadingError":
-		if error, ok := data.PropertyValue("error"); ok {
-			ErrorLog(error)
-		}
-		if index, ok := dataIntProperty(data, "index"); ok {
-			if result, ok := picker.loader[index]; ok {
-				if index >= 0 && index < len(picker.files) {
-					result(picker.files[index], nil)
-				} else {
-					result(FileInfo{}, nil)
-				}
-				delete(picker.loader, index)
-			}
-		}
-		return true
 	}
 
 	return picker.viewData.handleCommand(self, command, data)
@@ -354,7 +334,7 @@ func GetFilePickerAccept(view View, subviewID ...string) []string {
 		}
 		if ok {
 			result := strings.Split(accept, ",")
-			for i := 0; i < len(result); i++ {
+			for i := range len(result) {
 				result[i] = strings.Trim(result[i], " \t\n")
 			}
 			return result

filter.go

@@ -159,7 +159,7 @@ func NewFilterProperty(params Params) FilterProperty {
 func newFilterProperty(obj DataObject) FilterProperty {
 	filter := new(filterData)
 	filter.init()
-	for i := 0; i < obj.PropertyCount(); i++ {
+	for i := range obj.PropertyCount() {
 		if node := obj.Property(i); node != nil {
 			tag := node.Tag()
 			switch node.Type() {

listLayout.go

@@ -176,8 +176,7 @@ func (listLayout *listLayoutData) createContent() bool {
 		htmlID := listLayout.htmlID()
 		isDisabled := IsDisabled(listLayout)
 
-		count := adapter.ListSize()
-		for i := 0; i < count; i++ {
+		for i := range adapter.ListSize() {
 			if view := adapter.ListItem(i, session); view != nil {
 				view.setParentID(htmlID)
 				if isDisabled {

listView.go

@@ -428,7 +428,7 @@ func (listView *listViewData) ReloadListViewData() {
 			listView.itemFrame = make([]Frame, itemCount)
 		}
 
-		for i := 0; i < itemCount; i++ {
+		for i := range itemCount {
 			listView.items[i] = adapter.ListItem(i, listView.Session())
 		}
 	} else if len(listView.items) > 0 {
@@ -632,7 +632,7 @@ func (listView *listViewData) checkboxSubviews(adapter ListAdapter, buffer *stri
 
 	current := GetCurrent(listView)
 	checkedItems := GetListViewCheckedItems(listView)
-	for i := 0; i < count; i++ {
+	for i := range count {
 		buffer.WriteString(`<div id="`)
 		buffer.WriteString(listViewID)
 		buffer.WriteRune('-')
@@ -693,7 +693,7 @@ func (listView *listViewData) noneCheckboxSubviews(adapter ListAdapter, buffer *
 	itemStyle := itemStyleBuilder.String()
 
 	current := GetCurrent(listView)
-	for i := 0; i < count; i++ {
+	for i := range count {
 		buffer.WriteString(`<div id="`)
 		buffer.WriteString(listViewID)
 		buffer.WriteRune('-')

popup.go

@@ -740,7 +740,7 @@ func (popup *popupData) init(view View, popupParams Params) {
 		popupCellHeight = append(popupCellHeight, AutoSize())
 		gap, _ := sizeConstant(session, "ruiPopupButtonGap")
 		cellWidth := []SizeUnit{}
-		for i := 0; i < buttonCount; i++ {
+		for range buttonCount {
 			cellWidth = append(cellWidth, Fr(1))
 		}
 

properties.go

@@ -121,7 +121,7 @@ func (properties *propertyList) writeToBuffer(buffer *strings.Builder,
 
 func parseProperties(properties Properties, object DataObject) {
 	count := object.PropertyCount()
-	for i := 0; i < count; i++ {
+	for i := range count {
 		if node := object.Property(i); node != nil {
 			switch node.Type() {
 			case TextNode:

session.go

@@ -734,7 +734,7 @@ func (session *sessionData) handleSessionInfo(params DataObject) {
 
 	if node := params.PropertyByTag("storage"); node != nil && node.Type() == ObjectNode {
 		if obj := node.Object(); obj != nil {
-			for i := 0; i < obj.PropertyCount(); i++ {
+			for i := range obj.PropertyCount() {
 				if element := obj.Property(i); element.Type() == TextNode {
 					session.clientStorage[element.Tag()] = element.Text()
 				}

strings.go

@@ -61,7 +61,7 @@ func loadStringResources(text string) {
 			table = map[string]string{}
 		}
 
-		for i := 0; i < obj.PropertyCount(); i++ {
+		for i := range obj.PropertyCount() {
 			if prop := obj.Property(i); prop != nil && prop.Type() == TextNode {
 				table[prop.Tag()] = prop.Text()
 			}
@@ -72,7 +72,7 @@ func loadStringResources(text string) {
 
 	tag := data.Tag()
 	if tag == "strings" {
-		for i := 0; i < data.PropertyCount(); i++ {
+		for i := range data.PropertyCount() {
 			if prop := data.Property(i); prop != nil && prop.Type() == ObjectNode {
 				parseStrings(prop.Object(), prop.Tag())
 			}

tableView.go

@@ -739,7 +739,7 @@ func (table *tableViewData) setFunc(tag PropertyName, value any) []PropertyName
 
 		case DataObject:
 			params := Params{}
-			for k := 0; k < value.PropertyCount(); k++ {
+			for k := range value.PropertyCount() {
 				if prop := value.Property(k); prop != nil && prop.Type() == TextNode {
 					params[PropertyName(prop.Tag())] = prop.Text()
 				}
@@ -797,7 +797,7 @@ func (table *tableViewData) setFunc(tag PropertyName, value any) []PropertyName
 			if strings.Contains(value, ",") {
 				if values := strings.Split(value, ","); len(values) == 2 {
 					var n = []int{0, 0}
-					for i := 0; i < 2; i++ {
+					for i := range 2 {
 						var err error
 						if n[i], err = strconv.Atoi(values[i]); err != nil {
 							ErrorLog(err.Error())

theme.go

@@ -695,7 +695,7 @@ func (theme *theme) addText(themeText string) bool {
 
 	objToStyle := func(obj DataObject) ViewStyle {
 		params := Params{}
-		for i := 0; i < obj.PropertyCount(); i++ {
+		for i := range obj.PropertyCount() {
 			if node := obj.Property(i); node != nil {
 				switch node.Type() {
 				case ArrayNode:
@@ -712,14 +712,14 @@ func (theme *theme) addText(themeText string) bool {
 		return NewViewStyle(params)
 	}
 
-	for i := 0; i < count; i++ {
+	for i := range count {
 		if d := data.Property(i); d != nil {
 			switch tag := d.Tag(); tag {
 			case "constants":
 				if d.Type() == ObjectNode {
 					if obj := d.Object(); obj != nil {
 						objCount := obj.PropertyCount()
-						for k := 0; k < objCount; k++ {
+						for k := range objCount {
 							if prop := obj.Property(k); prop != nil && prop.Type() == TextNode {
 								theme.constants[prop.Tag()] = prop.Text()
 							}
@@ -731,7 +731,7 @@ func (theme *theme) addText(themeText string) bool {
 				if d.Type() == ObjectNode {
 					if obj := d.Object(); obj != nil {
 						objCount := obj.PropertyCount()
-						for k := 0; k < objCount; k++ {
+						for k := range objCount {
 							if prop := obj.Property(k); prop != nil && prop.Type() == TextNode {
 								theme.touchConstants[prop.Tag()] = prop.Text()
 							}
@@ -743,7 +743,7 @@ func (theme *theme) addText(themeText string) bool {
 				if d.Type() == ObjectNode {
 					if obj := d.Object(); obj != nil {
 						objCount := obj.PropertyCount()
-						for k := 0; k < objCount; k++ {
+						for k := range objCount {
 							if prop := obj.Property(k); prop != nil && prop.Type() == TextNode {
 								theme.colors[prop.Tag()] = prop.Text()
 							}
@@ -755,7 +755,7 @@ func (theme *theme) addText(themeText string) bool {
 				if d.Type() == ObjectNode {
 					if obj := d.Object(); obj != nil {
 						objCount := obj.PropertyCount()
-						for k := 0; k < objCount; k++ {
+						for k := range objCount {
 							if prop := obj.Property(k); prop != nil && prop.Type() == TextNode {
 								theme.darkColors[prop.Tag()] = prop.Text()
 							}
@@ -767,7 +767,7 @@ func (theme *theme) addText(themeText string) bool {
 				if d.Type() == ObjectNode {
 					if obj := d.Object(); obj != nil {
 						objCount := obj.PropertyCount()
-						for k := 0; k < objCount; k++ {
+						for k := range objCount {
 							if prop := obj.Property(k); prop != nil && prop.Type() == TextNode {
 								theme.images[prop.Tag()] = prop.Text()
 							}
@@ -779,7 +779,7 @@ func (theme *theme) addText(themeText string) bool {
 				if d.Type() == ObjectNode {
 					if obj := d.Object(); obj != nil {
 						objCount := obj.PropertyCount()
-						for k := 0; k < objCount; k++ {
+						for k := range objCount {
 							if prop := obj.Property(k); prop != nil && prop.Type() == TextNode {
 								theme.darkImages[prop.Tag()] = prop.Text()
 							}
@@ -790,7 +790,7 @@ func (theme *theme) addText(themeText string) bool {
 			case "styles":
 				if d.Type() == ArrayNode {
 					arraySize := d.ArraySize()
-					for k := 0; k < arraySize; k++ {
+					for k := range arraySize {
 						if element := d.ArrayElement(k); element != nil && element.IsObject() {
 							if obj := element.Object(); obj != nil {
 								theme.styles[obj.Tag()] = objToStyle(obj)
@@ -803,7 +803,7 @@ func (theme *theme) addText(themeText string) bool {
 				if d.Type() == ArrayNode && strings.HasPrefix(tag, "styles:") {
 					if rule, ok := parseMediaRule(tag); ok {
 						arraySize := d.ArraySize()
-						for k := 0; k < arraySize; k++ {
+						for k := range arraySize {
 							if element := d.ArrayElement(k); element != nil && element.IsObject() {
 								if obj := element.Object(); obj != nil {
 									rule.styles[obj.Tag()] = objToStyle(obj)

touchEvents.go

@@ -155,7 +155,7 @@ func (event *TouchEvent) init(data DataObject) {
 	event.Touches = []Touch{}
 	event.TimeStamp = getTimeStamp(data)
 	if node := data.PropertyByTag("touches"); node != nil && node.Type() == ArrayNode {
-		for i := 0; i < node.ArraySize(); i++ {
+		for i := range node.ArraySize() {
 			if element := node.ArrayElement(i); element != nil && element.IsObject() {
 				if obj := element.Object(); obj != nil {
 					var touch Touch

transform.go

@@ -369,7 +369,7 @@ func valueToTransformProperty(value any) TransformProperty {
 	parseObject := func(obj DataObject) TransformProperty {
 		transform := NewTransformProperty(nil)
 		ok := true
-		for i := 0; i < obj.PropertyCount(); i++ {
+		for i := range obj.PropertyCount() {
 			if prop := obj.Property(i); prop.Type() == TextNode {
 				if !transform.Set(PropertyName(prop.Tag()), prop.Text()) {
 					ok = false

utils.go

@@ -105,3 +105,12 @@ func InlineImageFromResource(filename string) (string, bool) {
 
 	return "", false
 }
+
+// InlineFileFromData creates inline image from the image data and mimetype.
+func InlineFileFromData(data []byte, mimeType string) string {
+	if data == nil {
+		return ""
+	}
+
+	return "data:" + mimeType + ";base64," + base64.StdEncoding.EncodeToString(data)
+}

view.go

@@ -1,6 +1,7 @@
 package rui
 
 import (
+	"encoding/base64"
 	"fmt"
 	"maps"
 	"strconv"
@@ -71,6 +72,12 @@ type View interface {
 	// HasFocus returns 'true' if the view has focus
 	HasFocus() bool
 
+	// LoadFile loads the content of the dropped file by drag-and-drop mechanism for all views except FilePicker.
+	// The selected file is loaded for FilePicker view.
+	//
+	// This function is asynchronous. The "result" function will be called after loading the data.
+	LoadFile(file FileInfo, result func(FileInfo, []byte))
+
 	init(session Session)
 	handleCommand(self View, command PropertyName, data DataObject) bool
 	htmlClass(disabled bool) string
@@ -115,6 +122,7 @@ type viewData struct {
 	set              func(tag PropertyName, value any) []PropertyName
 	remove           func(tag PropertyName) []PropertyName
 	changed          func(tag PropertyName)
+	fileLoader       map[string]func(FileInfo, []byte)
 }
 
 func newView(session Session) View {
@@ -160,6 +168,7 @@ func (view *viewData) init(session Session) {
 	view.noResizeEvent = false
 	view.created = false
 	view.hasHtmlDisabled = false
+	view.fileLoader = map[string]func(FileInfo, []byte){}
 }
 
 func (view *viewData) Session() Session {
@@ -1179,6 +1188,42 @@ func (view *viewData) handleCommand(self View, command PropertyName, data DataOb
 				self.onResize(self, floatProperty("x"), floatProperty("y"), floatProperty("width"), floatProperty("height"))
 				return true
 		*/
+
+	case "fileLoaded":
+		file := dataToFileInfo(data)
+		key := file.key()
+
+		if listener := view.fileLoader[key]; listener != nil {
+			delete(view.fileLoader, key)
+
+			if base64Data, ok := data.PropertyValue("data"); ok {
+				if index := strings.LastIndex(base64Data, ","); index >= 0 {
+					base64Data = base64Data[index+1:]
+				}
+				decode, err := base64.StdEncoding.DecodeString(base64Data)
+				if err == nil {
+					listener(file, decode)
+				} else {
+					ErrorLog(err.Error())
+				}
+			}
+		}
+		return true
+
+	case "fileLoadingError":
+		file := dataToFileInfo(data)
+		key := file.key()
+
+		if error, ok := data.PropertyValue("error"); ok {
+			ErrorLogF(`Load "%s" file error: %s`, file.Name, error)
+		}
+
+		if listener := view.fileLoader[key]; listener != nil {
+			delete(view.fileLoader, key)
+			listener(file, nil)
+		}
+		return true
+
 	default:
 		return false
 	}

viewStyleSet.go

@@ -64,7 +64,7 @@ func setTransitionProperty(properties Properties, value any) bool {
 			return false
 
 		case ArrayNode:
-			for i := 0; i < value.ArraySize(); i++ {
+			for i := range value.ArraySize() {
 				if obj := value.ArrayElement(i).Object(); obj != nil {
 					if !setObject(obj) {
 						return false
@@ -133,7 +133,7 @@ func setTransitionProperty(properties Properties, value any) bool {
 
 			case ArrayNode:
 				result := true
-				for i := 0; i < value.ArraySize(); i++ {
+				for i := range value.ArraySize() {
 					if obj := value.ArrayElement(i).Object(); obj != nil {
 						result = setObject(obj) && result
 					} else {