diff --git a/animation.go b/animation.go
index 68d222e..e8d7ead 100644
--- a/animation.go
+++ b/animation.go
@@ -245,14 +245,12 @@ func parseAnimation(obj DataObject) AnimationProperty {
 	animation := new(animationData)
 	animation.init()
 
-	for i := range obj.PropertyCount() {
-		if node := obj.Property(i); node != nil {
-			tag := PropertyName(node.Tag())
-			if node.Type() == TextNode {
-				animation.Set(tag, node.Text())
-			} else {
-				animation.Set(tag, node)
-			}
+	for node := range obj.Properties() {
+		tag := PropertyName(node.Tag())
+		if node.Type() == TextNode {
+			animation.Set(tag, node.Text())
+		} else {
+			animation.Set(tag, node)
 		}
 	}
 	return animation
@@ -493,8 +491,8 @@ func animationSet(properties Properties, tag PropertyName, value any) []Property
 		case DataNode:
 			parseObject := func(obj DataObject) (AnimatedProperty, bool) {
 				result := AnimatedProperty{}
-				for i := range obj.PropertyCount() {
-					if node := obj.Property(i); node.Type() == TextNode {
+				for node := range obj.Properties() {
+					if node.Type() == TextNode {
 						propTag := strings.ToLower(node.Tag())
 						switch propTag {
 						case "from", "0", "0%":
diff --git a/background.go b/background.go
index 920064b..7e50655 100644
--- a/background.go
+++ b/background.go
@@ -66,9 +66,8 @@ func createBackground(obj DataObject) BackgroundElement {
 		return nil
 	}
 
-	count := obj.PropertyCount()
-	for i := range count {
-		if node := obj.Property(i); node.Type() == TextNode {
+	for node := range obj.Properties() {
+		if node.Type() == TextNode {
 			if value := node.Text(); value != "" {
 				result.Set(PropertyName(node.Tag()), value)
 			}
diff --git a/border.go b/border.go
index 08be325..23f7cd1 100644
--- a/border.go
+++ b/border.go
@@ -436,24 +436,20 @@ func (border *borderProperty) String() string {
 
 func (border *borderProperty) setBorderObject(obj DataObject) bool {
 	result := true
-	for i := range obj.PropertyCount() {
-		if node := obj.Property(i); node != nil {
-			tag := PropertyName(node.Tag())
-			switch node.Type() {
-			case TextNode:
-				if borderSet(border, tag, node.Text()) == nil {
-					result = false
-				}
-
-			case ObjectNode:
-				if borderSet(border, tag, node.Object()) == nil {
-					result = false
-				}
-
-			default:
+	for node := range obj.Properties() {
+		tag := PropertyName(node.Tag())
+		switch node.Type() {
+		case TextNode:
+			if borderSet(border, tag, node.Text()) == nil {
 				result = false
 			}
-		} else {
+
+		case ObjectNode:
+			if borderSet(border, tag, node.Object()) == nil {
+				result = false
+			}
+
+		default:
 			result = false
 		}
 	}
diff --git a/data.go b/data.go
index edc6998..ff06a30 100644
--- a/data.go
+++ b/data.go
@@ -3,6 +3,7 @@ package rui
 import (
 	"errors"
 	"fmt"
+	"iter"
 	"slices"
 	"strings"
 	"unicode"
@@ -27,6 +28,9 @@ type DataObject interface {
 	// Tag returns data object tag
 	Tag() string
 
+	// Properties() returns an iterator to access the properties
+	Properties() iter.Seq[DataNode]
+
 	// PropertyCount returns properties count
 	PropertyCount() int
 
@@ -142,6 +146,16 @@ func (object *dataObject) Tag() string {
 	return object.tag
 }
 
+func (object *dataObject) Properties() iter.Seq[DataNode] {
+	return func(yield func(DataNode) bool) {
+		for _, node := range object.property {
+			if !yield(node) {
+				return
+			}
+		}
+	}
+}
+
 func (object *dataObject) PropertyCount() int {
 	if object.property != nil {
 		return len(object.property)
@@ -231,10 +245,14 @@ func (object *dataObject) SetPropertyValue(tag, value string) {
 
 // SetPropertyObject - set a property with tag by object
 func (object *dataObject) SetPropertyObject(tag string, obj DataObject) {
-	node := new(dataNode)
-	node.tag = tag
-	node.value = obj
-	object.setNode(node)
+	if obj != nil {
+		node := new(dataNode)
+		node.tag = tag
+		node.value = obj
+		object.setNode(node)
+	} else {
+		object.RemovePropertyByTag(tag)
+	}
 }
 
 func (object *dataObject) ToParams() Params {
diff --git a/filter.go b/filter.go
index 887f953..89b1568 100644
--- a/filter.go
+++ b/filter.go
@@ -159,23 +159,21 @@ func NewFilterProperty(params Params) FilterProperty {
 func newFilterProperty(obj DataObject) FilterProperty {
 	filter := new(filterData)
 	filter.init()
-	for i := range obj.PropertyCount() {
-		if node := obj.Property(i); node != nil {
-			tag := node.Tag()
-			switch node.Type() {
-			case TextNode:
-				filter.Set(PropertyName(tag), node.Text())
+	for node := range obj.Properties() {
+		tag := node.Tag()
+		switch node.Type() {
+		case TextNode:
+			filter.Set(PropertyName(tag), node.Text())
 
-			case ObjectNode:
-				if tag == string(HueRotate) {
-					// TODO
-				} else {
-					ErrorLog(`Invalid value of "` + tag + `"`)
-				}
-
-			default:
+		case ObjectNode:
+			if tag == string(HueRotate) {
+				// TODO
+			} else {
 				ErrorLog(`Invalid value of "` + tag + `"`)
 			}
+
+		default:
+			ErrorLog(`Invalid value of "` + tag + `"`)
 		}
 	}
 
diff --git a/properties.go b/properties.go
index f0814a3..c71dd23 100644
--- a/properties.go
+++ b/properties.go
@@ -118,19 +118,16 @@ func (properties *propertyList) writeToBuffer(buffer *strings.Builder,
 }
 
 func parseProperties(properties Properties, object DataObject) {
-	count := object.PropertyCount()
-	for i := range count {
-		if node := object.Property(i); node != nil {
-			switch node.Type() {
-			case TextNode:
-				properties.Set(PropertyName(node.Tag()), node.Text())
+	for node := range object.Properties() {
+		switch node.Type() {
+		case TextNode:
+			properties.Set(PropertyName(node.Tag()), node.Text())
 
-			case ObjectNode:
-				properties.Set(PropertyName(node.Tag()), node.Object())
+		case ObjectNode:
+			properties.Set(PropertyName(node.Tag()), node.Object())
 
-			case ArrayNode:
-				properties.Set(PropertyName(node.Tag()), node.ArrayElements())
-			}
+		case ArrayNode:
+			properties.Set(PropertyName(node.Tag()), node.ArrayElements())
 		}
 	}
 }
diff --git a/session.go b/session.go
index 5c92551..d828160 100644
--- a/session.go
+++ b/session.go
@@ -735,8 +735,8 @@ func (session *sessionData) handleSessionInfo(params DataObject) {
 
 	if node := params.PropertyByTag("storage"); node != nil && node.Type() == ObjectNode {
 		if obj := node.Object(); obj != nil {
-			for i := range obj.PropertyCount() {
-				if element := obj.Property(i); element.Type() == TextNode {
+			for element := range obj.Properties() {
+				if element.Type() == TextNode {
 					session.clientStorage[element.Tag()] = element.Text()
 				}
 			}
diff --git a/strings.go b/strings.go
index 090ecd9..fa023cb 100644
--- a/strings.go
+++ b/strings.go
@@ -62,8 +62,8 @@ func loadStringResources(text string) {
 			table = map[string]string{}
 		}
 
-		for i := range obj.PropertyCount() {
-			if prop := obj.Property(i); prop != nil && prop.Type() == TextNode {
+		for prop := range obj.Properties() {
+			if prop.Type() == TextNode {
 				table[prop.Tag()] = prop.Text()
 			}
 		}
@@ -73,8 +73,8 @@ func loadStringResources(text string) {
 
 	tag := data.Tag()
 	if tag == "strings" {
-		for i := range data.PropertyCount() {
-			if prop := data.Property(i); prop != nil && prop.Type() == ObjectNode {
+		for prop := range data.Properties() {
+			if prop.Type() == ObjectNode {
 				parseStrings(prop.Object(), prop.Tag())
 			}
 		}
diff --git a/tableView.go b/tableView.go
index 8f198e1..4e59f0e 100644
--- a/tableView.go
+++ b/tableView.go
@@ -731,8 +731,8 @@ func (table *tableViewData) setFunc(tag PropertyName, value any) []PropertyName
 
 		case DataObject:
 			params := Params{}
-			for k := range value.PropertyCount() {
-				if prop := value.Property(k); prop != nil && prop.Type() == TextNode {
+			for prop := range value.Properties() {
+				if prop.Type() == TextNode {
 					params[PropertyName(prop.Tag())] = prop.Text()
 				}
 			}
diff --git a/theme.go b/theme.go
index 03870dc..eb3d080 100644
--- a/theme.go
+++ b/theme.go
@@ -694,127 +694,115 @@ func (theme *theme) addText(themeText string) bool {
 		return false
 	}
 
-	count := data.PropertyCount()
-
 	objToStyle := func(obj DataObject) ViewStyle {
 		params := Params{}
-		for i := range obj.PropertyCount() {
-			if node := obj.Property(i); node != nil {
-				switch node.Type() {
-				case ArrayNode:
-					params[PropertyName(node.Tag())] = node.ArrayElements()
+		for node := range obj.Properties() {
+			switch node.Type() {
+			case ArrayNode:
+				params[PropertyName(node.Tag())] = node.ArrayElements()
 
-				case ObjectNode:
-					params[PropertyName(node.Tag())] = node.Object()
+			case ObjectNode:
+				params[PropertyName(node.Tag())] = node.Object()
 
-				default:
-					params[PropertyName(node.Tag())] = node.Text()
-				}
+			default:
+				params[PropertyName(node.Tag())] = node.Text()
 			}
 		}
 		return NewViewStyle(params)
 	}
 
-	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 := range objCount {
-							if prop := obj.Property(k); prop != nil && prop.Type() == TextNode {
-								theme.constants[prop.Tag()] = prop.Text()
-							}
+	for d := range data.Properties() {
+		switch tag := d.Tag(); tag {
+		case "constants":
+			if d.Type() == ObjectNode {
+				if obj := d.Object(); obj != nil {
+					for prop := range obj.Properties() {
+						if prop.Type() == TextNode {
+							theme.constants[prop.Tag()] = prop.Text()
 						}
 					}
 				}
+			}
 
-			case "constants:touch":
-				if d.Type() == ObjectNode {
-					if obj := d.Object(); obj != nil {
-						objCount := obj.PropertyCount()
-						for k := range objCount {
-							if prop := obj.Property(k); prop != nil && prop.Type() == TextNode {
-								theme.touchConstants[prop.Tag()] = prop.Text()
-							}
+		case "constants:touch":
+			if d.Type() == ObjectNode {
+				if obj := d.Object(); obj != nil {
+					for prop := range obj.Properties() {
+						if prop.Type() == TextNode {
+							theme.touchConstants[prop.Tag()] = prop.Text()
 						}
 					}
 				}
+			}
 
-			case "colors":
-				if d.Type() == ObjectNode {
-					if obj := d.Object(); obj != nil {
-						objCount := obj.PropertyCount()
-						for k := range objCount {
-							if prop := obj.Property(k); prop != nil && prop.Type() == TextNode {
-								theme.colors[prop.Tag()] = prop.Text()
-							}
+		case "colors":
+			if d.Type() == ObjectNode {
+				if obj := d.Object(); obj != nil {
+					for prop := range obj.Properties() {
+						if prop.Type() == TextNode {
+							theme.colors[prop.Tag()] = prop.Text()
 						}
 					}
 				}
+			}
 
-			case "colors:dark":
-				if d.Type() == ObjectNode {
-					if obj := d.Object(); obj != nil {
-						objCount := obj.PropertyCount()
-						for k := range objCount {
-							if prop := obj.Property(k); prop != nil && prop.Type() == TextNode {
-								theme.darkColors[prop.Tag()] = prop.Text()
-							}
+		case "colors:dark":
+			if d.Type() == ObjectNode {
+				if obj := d.Object(); obj != nil {
+					for prop := range obj.Properties() {
+						if prop.Type() == TextNode {
+							theme.darkColors[prop.Tag()] = prop.Text()
 						}
 					}
 				}
+			}
 
-			case "images":
-				if d.Type() == ObjectNode {
-					if obj := d.Object(); obj != nil {
-						objCount := obj.PropertyCount()
-						for k := range objCount {
-							if prop := obj.Property(k); prop != nil && prop.Type() == TextNode {
-								theme.images[prop.Tag()] = prop.Text()
-							}
+		case "images":
+			if d.Type() == ObjectNode {
+				if obj := d.Object(); obj != nil {
+					for prop := range obj.Properties() {
+						if prop.Type() == TextNode {
+							theme.images[prop.Tag()] = prop.Text()
 						}
 					}
 				}
+			}
 
-			case "images:dark":
-				if d.Type() == ObjectNode {
-					if obj := d.Object(); obj != nil {
-						objCount := obj.PropertyCount()
-						for k := range objCount {
-							if prop := obj.Property(k); prop != nil && prop.Type() == TextNode {
-								theme.darkImages[prop.Tag()] = prop.Text()
-							}
+		case "images:dark":
+			if d.Type() == ObjectNode {
+				if obj := d.Object(); obj != nil {
+					for prop := range obj.Properties() {
+						if prop.Type() == TextNode {
+							theme.darkImages[prop.Tag()] = prop.Text()
 						}
 					}
 				}
+			}
 
-			case "styles":
-				if d.Type() == ArrayNode {
+		case "styles":
+			if d.Type() == ArrayNode {
+				arraySize := d.ArraySize()
+				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)
+						}
+					}
+				}
+			}
+
+		default:
+			if d.Type() == ArrayNode && strings.HasPrefix(tag, "styles:") {
+				if rule, ok := parseMediaRule(tag); ok {
 					arraySize := d.ArraySize()
 					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)
+								rule.styles[obj.Tag()] = objToStyle(obj)
 							}
 						}
 					}
-				}
-
-			default:
-				if d.Type() == ArrayNode && strings.HasPrefix(tag, "styles:") {
-					if rule, ok := parseMediaRule(tag); ok {
-						arraySize := d.ArraySize()
-						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)
-								}
-							}
-						}
-						theme.mediaStyles = append(theme.mediaStyles, rule)
-					}
+					theme.mediaStyles = append(theme.mediaStyles, rule)
 				}
 			}
 		}
diff --git a/transform.go b/transform.go
index f359e38..7807bd9 100644
--- a/transform.go
+++ b/transform.go
@@ -352,8 +352,8 @@ func valueToTransformProperty(value any) TransformProperty {
 	parseObject := func(obj DataObject) TransformProperty {
 		transform := NewTransformProperty(nil)
 		ok := true
-		for i := range obj.PropertyCount() {
-			if prop := obj.Property(i); prop.Type() == TextNode {
+		for prop := range obj.Properties() {
+			if prop.Type() == TextNode {
 				if !transform.Set(PropertyName(prop.Tag()), prop.Text()) {
 					ok = false
 				}
diff --git a/view.go b/view.go
index e1d1afc..9f03e5f 100644
--- a/view.go
+++ b/view.go
@@ -371,8 +371,7 @@ func (view *viewData) setFunc(tag PropertyName, value any) []PropertyName {
 	case changeListeners:
 		switch value := value.(type) {
 		case DataObject:
-			for i := range value.PropertyCount() {
-				node := value.Property(i)
+			for node := range value.Properties() {
 				if node.Type() == TextNode {
 					if text := node.Text(); text != "" {
 						view.changeListener[PropertyName(node.Tag())] = newOneArgListenerBinding[View, PropertyName](text)
@@ -496,9 +495,7 @@ func (view *viewData) setFunc(tag PropertyName, value any) []PropertyName {
 
 		case DataObject:
 			data := map[string]string{}
-			count := value.PropertyCount()
-			for i := range count {
-				node := value.Property(i)
+			for node := range value.Properties() {
 				if node.Type() == TextNode {
 					data[node.Tag()] = node.Text()
 				} else {