Added "drop-effect-allowed" property

app_scripts.js

@@ -2144,10 +2144,10 @@ function dragAndDropEvent(element, event, tag) {
 	//event.preventDefault()
 
 	let message = tag + "{session=" + sessionID + ",id=" + element.id + mouseEventData(element, event);
+	if (event.target) {
+		message += ",target=" + event.target.id;
+	}
 	if (event.dataTransfer) {
-		if (event.target) {
-			message += ",target=" + event.target.id;
-		}
 		let dataText = ""
 		for (const item of event.dataTransfer.items) {
 			const data = event.dataTransfer.getData(item.type);
@@ -2161,7 +2161,25 @@ function dragAndDropEvent(element, event, tag) {
 		if (dataText != "") {
 			message += ',data="' + dataText + '"';
 		}
+
+		dataText = ""
+		for (const file of event.dataTransfer.files) {
+			if (dataText != "") {
+				dataText += ";";
+			}
+			dataText += file.name;
+		}
+		if (dataText != "") {
+			message += ',files="' + dataText + '"';
+		}
+		if (event.dataTransfer.effectAllowed && event.dataTransfer.effectAllowed != "uninitialized") {
+			message += ',effect-allowed="' + event.dataTransfer.effectAllowed + '"';
+		}
+		if (event.dataTransfer.dropEffect) {
+			message += ',drop-effect="' + event.dataTransfer.dropEffect + '"';
+		}
 	}
+
 	message += "}";
 	sendMessage(message);
 }
@@ -2193,14 +2211,12 @@ function dragStartEvent(element, event) {
 		let img = new Image();
   		img.src = image;
 		event.dataTransfer.setDragImage(img, x, y);
-
-		let effect = element.getAttribute("data-drag-effect");
-		if (effect) {
-			event.dataTransfer.effectAllowed = effect;
-		}
 	}
 
-	// TODO drag effect
+	let allowed = element.getAttribute("data-drop-effect-allowed");
+	if (allowed) {
+		event.dataTransfer.effectAllowed = allowed;
+	}
 
 	dragAndDropEvent(element, event, "drag-start-event");
 }
@@ -2210,6 +2226,11 @@ function dragEndEvent(element, event) {
 }
 
 function dragEnterEvent(element, event) {
+	let effect = element.getAttribute("data-drop-effect");
+	if (effect) {
+		event.dataTransfer.dropEffect = effect;
+	}
+
 	dragAndDropEvent(element, event, "drag-enter-event")
 }
 

dragAndDrop.go

@@ -39,7 +39,23 @@ const (
 	// Supported types: float, int, string.
 	DragImageYOffset PropertyName = "drag-image-y-offset"
 
-	// DragEffect is the constant for "drag-effect" property tag.
+	// DropEffect is the constant for "drag-effect" property tag.
+	//
+	// Used by View.
+	// Controls the feedback (typically visual) the user is given during a drag and drop operation.
+	// It will affect which cursor is displayed while dragging. For example, when the user hovers over a target drop element,
+	// the browser's cursor may indicate which type of operation will occur.
+	//
+	// Supported types: int, string.
+	//
+	// Values:
+	//   - 0 (DropEffectUndefined) or "undefined" - The property value is not defined (defaut 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.
+	DropEffect PropertyName = "drag-effect"
+
+	// DropEffectAllowed is the constant for "drop-effect-allowed" property tag.
 	//
 	// Used by View.
 	// Specifies the effect that is allowed for a drag operation.
@@ -52,15 +68,15 @@ const (
 	// Supported types: int, string.
 	//
 	// Values:
-	//   - 0 (DragEffectAll) or "all" - All operations are permitted (defaut value).
+	//   - 0 (DropEffectUndefined) or "undefined" - The property value is not defined (defaut value). Equivalent to DropEffectAll
-	//   - 1 (DragEffectCopy) or "copy" - A copy of the source item may be made at the new location.
+	//   - 1 (DropEffectCopy) or "copy" - A copy of the source item may be made at the new location.
-	//   - 2 (DragEffectMove) or "move" - An item may be moved to a new location.
+	//   - 2 (DropEffectMove) or "move" - An item may be moved to a new location.
-	//   - 3 (DragEffectLink) or "link" - A link may be established to the source at the new location.
+	//   - 3 (DropEffectLink) or "link" - A link may be established to the source at the new location.
-	//   - 4 (DragEffectCopyMove) or "copyMove" - A copy or move operation is permitted.
+	//   - 4 (DropEffectCopyMove) or "copy|move" - A copy or move operation is permitted.
-	//   - 5 (DragEffectCopyLink) or "copyLink" - A copy or link operation is permitted.
+	//   - 5 (DropEffectCopyLink) or "copy|link" - A copy or link operation is permitted.
-	//   - 6 (DragEffectLinkMove) or "linkMove" - A link or move operation is permitted.
+	//   - 6 (DropEffectLinkMove) or "link|move" - A link or move operation is permitted.
-	//   - 7 (DragEffectNone) or "none" - The item may not be dropped.
+	//   - 7 (DropEffectAll) or "all" or "copy|move|link" - All operations are permitted.
-	DragEffect PropertyName = "drag-effect"
+	DropEffectAllowed PropertyName = "drag-effect-allowed"
 
 	// DragStartEvent is the constant for "drag-start-event" property tag.
 	//
@@ -116,36 +132,42 @@ const (
 	//
 	DropEvent PropertyName = "drop-event"
 
-	// DragEffectAll - the value of the "drag-effect" property: all operations (copy, move, and link) are permitted (defaut value).
+	// DropEffectUndefined - the value of the "drop-effect" and "drop-effect-allowed" properties: the value is not defined (default value).
-	DragEffectAll = 0
+	DropEffectUndefined = 0
 
-	// DragEffectCopy - the value of the "drag-effect" property: a copy of the source item may be made at the new location.
+	// DropEffectNone - the value of the DropEffect field of the DragEvent struct: the item may not be dropped.
-	DragEffectCopy = 1
+	DropEffectNone = 0
 
-	// DragEffectMove - the value of the "drag-effect" property: an item may be moved to a new location.
+	// DropEffectCopy - the value of the "drop-effect" and "drop-effect-allowed" properties: a copy of the source item may be made at the new location.
-	DragEffectMove = 2
+	DropEffectCopy = 1
 
-	// DragEffectLink - the value of the "drag-effect" property: a link may be established to the source at the new location.
+	// DropEffectMove - the value of the "drop-effect" and "drop-effect-allowed" properties: an item may be moved to a new location.
-	DragEffectLink = 3
+	DropEffectMove = 2
 
-	// DragEffectCopyMove - the value of the "drag-effect" property: a copy or move operation is permitted.
+	// DropEffectLink - the value of the "drop-effect" and "drop-effect-allowed" properties: a link may be established to the source at the new location.
-	DragEffectCopyMove = 4
+	DropEffectLink = 4
 
-	// DragEffectCopyLink - the value of the "drag-effect" property: a copy or link operation is permitted.
+	// DropEffectCopyMove - the value of the "drop-effect-allowed" property: a copy or move operation is permitted.
-	DragEffectCopyLink = 5
+	DropEffectCopyMove = DropEffectCopy + DropEffectMove
 
-	// DragEffectLinkMove - the value of the "drag-effect" property: a link or move operation is permitted.
+	// DropEffectCopyLink - the value of the "drop-effect-allowed" property: a copy or link operation is permitted.
-	DragEffectLinkMove = 6
+	DropEffectCopyLink = DropEffectCopy + DropEffectLink
 
-	// DragEffectNone - the value of the "drag-effect" property: the item may not be dropped.
+	// DropEffectLinkMove - the value of the "drop-effect-allowed" property: a link or move operation is permitted.
-	DragEffectNone = 7
+	DropEffectLinkMove = DropEffectLink + DropEffectMove
+
+	// DropEffectAll - the value of the "drop-effect-allowed" property: all operations (copy, move, and link) are permitted (defaut value).
+	DropEffectAll = DropEffectCopy + DropEffectMove + DropEffectLink
 )
 
 // MouseEvent represent a mouse event
 type DragAndDropEvent struct {
 	MouseEvent
-	Data   map[string]string
+	Data          map[string]string
-	Target View
+	Files         string
+	Target        View
+	EffectAllowed int
+	DropEffect    int
 }
 
 func (event *DragAndDropEvent) init(session Session, data DataObject) {
@@ -175,6 +197,136 @@ func (event *DragAndDropEvent) init(session Session, data DataObject) {
 	if targetId, ok := data.PropertyValue("target"); ok {
 		event.Target = session.viewByHTMLID(targetId)
 	}
+
+	if effect, ok := data.PropertyValue("effect-allowed"); ok {
+		for i, value := range []string{"undefined", "copy", "move", "copyMove", "link", "copyLink", "linkMove", "all"} {
+			if value == effect {
+				event.EffectAllowed = i
+				break
+			}
+		}
+	}
+
+	if effect, ok := data.PropertyValue("drop-effect"); ok && effect != "" {
+		for i, value := range []string{"none", "copy", "move", "", "link"} {
+			if value == effect {
+				event.DropEffect = i
+				break
+			}
+		}
+	}
+
+	// TODO files
+}
+
+func stringToDropEffect(text string) (int, bool) {
+	text = strings.Trim(text, " \t\n")
+	if n, ok := enumStringToInt(text, []string{"", "copy", "move", "", "link"}, false); ok {
+		switch n {
+		case DropEffectUndefined, DropEffectCopy, DropEffectMove, DropEffectLink:
+			return n, true
+		}
+	}
+	return 0, false
+}
+
+func (view *viewData) setDropEffect(value any) []PropertyName {
+	if !setSimpleProperty(view, DropEffect, value) {
+		if text, ok := value.(string); ok {
+
+			if n, ok := stringToDropEffect(text); ok {
+				if n == DropEffectUndefined {
+					view.setRaw(DropEffect, nil)
+				} else {
+					view.setRaw(DropEffect, n)
+				}
+			} else {
+				invalidPropertyValue(DropEffect, value)
+				return nil
+			}
+
+		} else if i, ok := isInt(value); ok {
+
+			switch i {
+			case DropEffectUndefined:
+				view.setRaw(DropEffect, nil)
+
+			case DropEffectCopy, DropEffectMove, DropEffectLink:
+				view.setRaw(DropEffect, i)
+
+			default:
+				invalidPropertyValue(DropEffect, value)
+				return nil
+			}
+
+		} else {
+
+			notCompatibleType(DropEffect, value)
+			return nil
+		}
+
+	}
+
+	return []PropertyName{DropEffect}
+}
+
+func stringToDropEffectAllowed(text string) (int, bool) {
+	if strings.Contains(text, "|") {
+		elements := strings.Split(text, "|")
+		result := 0
+		for _, element := range elements {
+			if n, ok := stringToDropEffect(element); ok && n != DropEffectUndefined {
+				result |= n
+			} else {
+				return 0, false
+			}
+		}
+		return result, true
+	}
+
+	text = strings.Trim(text, " \t\n")
+	if text != "" {
+		if n, ok := enumStringToInt(text, []string{"undefined", "copy", "move", "", "link", "", "", "all"}, false); ok {
+			return n, true
+		}
+	}
+	return 0, false
+}
+
+func (view *viewData) setDropEffectAllowed(value any) []PropertyName {
+	if !setSimpleProperty(view, DropEffectAllowed, value) {
+		if text, ok := value.(string); ok {
+
+			if n, ok := stringToDropEffectAllowed(text); ok {
+				if n == DropEffectUndefined {
+					view.setRaw(DropEffectAllowed, nil)
+				} else {
+					view.setRaw(DropEffectAllowed, n)
+				}
+			} else {
+				invalidPropertyValue(DropEffectAllowed, value)
+				return nil
+			}
+
+		} else {
+			n, ok := isInt(value)
+			if !ok {
+				notCompatibleType(DropEffectAllowed, value)
+				return nil
+			}
+
+			if n == DropEffectUndefined {
+				view.setRaw(DropEffectAllowed, nil)
+			} else if n > DropEffectUndefined && n <= DropEffectAll {
+				view.setRaw(DropEffectAllowed, n)
+			} else {
+				notCompatibleType(DropEffectAllowed, value)
+				return nil
+			}
+		}
+	}
+
+	return []PropertyName{DropEffectAllowed}
 }
 
 func handleDragAndDropEvents(view View, tag PropertyName, data DataObject) {
@@ -227,7 +379,26 @@ func dragAndDropHtml(view View, buffer *strings.Builder) {
 		buffer.WriteString(` ondragstart="dragStartEvent(this, event)" `)
 	}
 
-	viewEventsHtml[DragAndDropEvent](view, []PropertyName{DragEndEvent, DragEnterEvent, DragLeaveEvent}, buffer)
+	enterEvent := false
+	switch GetDropEffect(view) {
+	case DropEffectCopy:
+		buffer.WriteString(` data-drop-effect="copy" ondragenter="dragEnterEvent(this, event)"`)
+		enterEvent = true
+
+	case DropEffectMove:
+		buffer.WriteString(` data-drop-effect="move" ondragenter="dragEnterEvent(this, event)"`)
+		enterEvent = true
+
+	case DropEffectLink:
+		buffer.WriteString(` data-drop-effect="link" ondragenter="dragEnterEvent(this, event)"`)
+		enterEvent = true
+	}
+
+	if enterEvent {
+		viewEventsHtml[DragAndDropEvent](view, []PropertyName{DragEndEvent, DragLeaveEvent}, buffer)
+	} else {
+		viewEventsHtml[DragAndDropEvent](view, []PropertyName{DragEndEvent, DragEnterEvent, DragLeaveEvent}, buffer)
+	}
 
 	session := view.Session()
 	if img, ok := stringProperty(view, DragImage, session); ok && img != "" {
@@ -257,9 +428,9 @@ func dragAndDropHtml(view View, buffer *strings.Builder) {
 		buffer.WriteString(`" `)
 	}
 
-	effects := enumProperties[DragEffect].cssValues
+	effects := []string{"undifined", "copy", "move", "copyMove", "link", "copyLink", "linkMove", "all"}
-	if n := GetDragEffect(view); n > 0 && n < len(effects) {
+	if n := GetDropEffectAllowed(view); n > 0 && n < len(effects) {
-		buffer.WriteString(` data-drag-effect="`)
+		buffer.WriteString(` data-drop-effect-allowed="`)
 		buffer.WriteString(effects[n])
 		buffer.WriteString(`" `)
 	}
@@ -326,21 +497,84 @@ func GetDragImageYOffset(view View, subviewID ...string) float64 {
 	return floatStyledProperty(view, subviewID, DragImageYOffset, 0)
 }
 
-// GetDragEffect returns the effect that is allowed for a drag operation.
+// GetDropEffect returns the effect that is allowed for a drag operation.
+// Controls the feedback (typically visual) the user is given during a drag and drop operation.
+// It will affect which cursor is displayed while dragging.
+//
+// Returns one of next values:
+//   - 0 (DropEffectUndefined) - The value is not defined (all operations are permitted).
+//   - 1 (DropEffectCopy) - A copy of the source item may be made at the new location.
+//   - 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.
+func GetDropEffect(view View, subviewID ...string) int {
+	if view = getSubview(view, subviewID); view != nil {
+		value := view.getRaw(DropEffect)
+		if value == nil {
+			value = valueFromStyle(view, DropEffect)
+		}
+
+		if value != nil {
+			switch value := value.(type) {
+			case int:
+				return value
+
+			case string:
+				if value, ok := view.Session().resolveConstants(value); ok {
+					if n, ok := stringToDropEffect(value); ok {
+						return n
+					}
+				}
+
+			default:
+				return DropEffectUndefined
+			}
+		}
+	}
+	return DropEffectUndefined
+}
+
+// GetDropEffectAllowed returns the effect that is allowed for a drag operation.
 // The copy operation is used to indicate that the data being dragged will be copied from its present location to the drop location.
 // The move operation is used to indicate that the data being dragged will be moved,
 // and the link operation is used to indicate that some form of relationship
-// or connection will be created between the source and drop locations.. Returns one of next values:
+// or connection will be created between the source and drop locations.
-//   - 0 (DragEffectAll) or "all" - All operations are permitted (defaut value).
+//
-//   - 1 (DragEffectCopy) or "copy" - A copy of the source item may be made at the new location.
+// Returns one of next values:
-//   - 2 (DragEffectMove) or "move" - An item may be moved to a new location.
+//   - 0 (DropEffectUndefined) - The value is not defined (all operations are permitted).
-//   - 3 (DragEffectLink) or "link" - A link may be established to the source at the new location.
+//   - 1 (DropEffectCopy) - A copy of the source item may be made at the new location.
-//   - 4 (DragEffectCopyMove) or "copyMove" - A copy or move operation is permitted.
+//   - 2 (DropEffectMove) - An item may be moved to a new location.
-//   - 5 (DragEffectCopyLink) or "copyLink" - A copy or link operation is permitted.
+//   - 4 (DropEffectLink) - A link may be established to the source at the new location.
-//   - 6 (DragEffectLinkMove) or "linkMove" - A link or move operation is permitted.
+//   - 3 (DropEffectCopyMove) - A copy or move operation is permitted.
-//   - 7 (DragEffectNone) or "none" - The item may not be dropped.
+//   - 5 (DropEffectCopyLink) - A copy or link operation is permitted.
+//   - 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.
-func GetDragEffect(view View, subviewID ...string) int {
+func GetDropEffectAllowed(view View, subviewID ...string) int {
-	return enumStyledProperty(view, subviewID, DragEffect, DragEffectAll, true)
+	if view = getSubview(view, subviewID); view != nil {
+		value := view.getRaw(DropEffectAllowed)
+		if value == nil {
+			value = valueFromStyle(view, DropEffectAllowed)
+		}
+
+		if value != nil {
+			switch value := value.(type) {
+			case int:
+				return value
+
+			case string:
+				if value, ok := view.Session().resolveConstants(value); ok {
+					if n, ok := stringToDropEffectAllowed(value); ok {
+						return n
+					}
+				}
+
+			default:
+				return DropEffectUndefined
+			}
+		}
+	}
+	return DropEffectUndefined
 }

editView.go

@@ -261,9 +261,9 @@ func (edit *editViewData) AppendText(text string) {
 				return
 			}
 		}
-		edit.setRaw(Text, text)
+		edit.Set(Text, text)
 	} else {
-		edit.setRaw(Text, GetText(edit)+text)
+		edit.Set(Text, GetText(edit)+text)
 	}
 }
 

propertySet.go

@@ -496,11 +496,6 @@ var enumProperties = map[PropertyName]enumPropertyData{
 		string(ColumnFill),
 		[]string{"balance", "auto"},
 	},
-	DragEffect: {
-		[]string{"all", "copy", "move", "link", "copyMove", "copyLink", "linkMove", "none"},
-		"",
-		[]string{"all", "copy", "move", "link", "copyMove", "copyLink", "linkMove", "none"},
-	},
 }
 
 func notCompatibleType(tag PropertyName, value any) {

view.go

@@ -479,6 +479,11 @@ func (view *viewData) setFunc(tag PropertyName, value any) []PropertyName {
 	case DragStartEvent, DragEndEvent, DragEnterEvent, DragLeaveEvent, DragOverEvent, DropEvent:
 		return setOneArgEventListener[View, DragAndDropEvent](view, tag, value)
 
+	case DropEffect:
+		return view.setDropEffect(value)
+
+	case DropEffectAllowed:
+		return view.setDropEffectAllowed(value)
 	}
 
 	return viewStyleSet(view, tag, value)
@@ -509,16 +514,16 @@ func (view *viewData) propertyChanged(tag PropertyName) {
 
 	switch tag {
 	case TabIndex:
-		if value, ok := intProperty(view, TabIndex, view.Session(), 0); ok {
+		if value, ok := intProperty(view, TabIndex, session, 0); ok {
-			session.updateProperty(view.htmlID(), "tabindex", strconv.Itoa(value))
+			session.updateProperty(htmlID, "tabindex", strconv.Itoa(value))
 		} else if view.Focusable() {
-			session.updateProperty(view.htmlID(), "tabindex", "0")
+			session.updateProperty(htmlID, "tabindex", "0")
 		} else {
-			session.updateProperty(view.htmlID(), "tabindex", "-1")
+			session.updateProperty(htmlID, "tabindex", "-1")
 		}
 
 	case Style, StyleDisabled:
-		session.updateProperty(view.htmlID(), "class", view.htmlClass(IsDisabled(view)))
+		session.updateProperty(htmlID, "class", view.htmlClass(IsDisabled(view)))
 
 	case Disabled:
 		tabIndex := GetTabIndex(view, htmlID)
@@ -775,7 +780,7 @@ func (view *viewData) propertyChanged(tag PropertyName) {
 
 	case PerspectiveOriginX, PerspectiveOriginY:
 		x, y := GetPerspectiveOrigin(view)
-		session.updateCSSProperty(htmlID, "perspective-origin", transformOriginCSS(x, y, AutoSize(), view.Session()))
+		session.updateCSSProperty(htmlID, "perspective-origin", transformOriginCSS(x, y, AutoSize(), session))
 
 	case BackfaceVisible:
 		if GetBackfaceVisible(view) {
@@ -786,7 +791,7 @@ func (view *viewData) propertyChanged(tag PropertyName) {
 
 	case TransformOriginX, TransformOriginY, TransformOriginZ:
 		x, y, z := getTransformOrigin(view, session)
-		session.updateCSSProperty(htmlID, "transform-origin", transformOriginCSS(x, y, z, view.Session()))
+		session.updateCSSProperty(htmlID, "transform-origin", transformOriginCSS(x, y, z, session))
 
 	case Transform:
 		css := ""
@@ -813,7 +818,7 @@ func (view *viewData) propertyChanged(tag PropertyName) {
 		if view.getRaw(DragStartEvent) != nil || view.getRaw(DragData) != nil {
 			session.updateProperty(htmlID, "ondragstart", "dragStartEvent(this, event)")
 		} else {
-			session.removeProperty(view.htmlID(), "ondragstart")
+			session.removeProperty(htmlID, "ondragstart")
 		}
 
 	case DropEvent:
@@ -823,18 +828,18 @@ func (view *viewData) propertyChanged(tag PropertyName) {
 			if view.getRaw(DragOverEvent) != nil {
 				session.updateProperty(htmlID, "data-drag-over", "1")
 			} else {
-				session.removeProperty(view.htmlID(), "data-drag-over")
+				session.removeProperty(htmlID, "data-drag-over")
 			}
 		} else {
-			session.removeProperty(view.htmlID(), "ondrop")
+			session.removeProperty(htmlID, "ondrop")
-			session.removeProperty(view.htmlID(), "ondragover")
+			session.removeProperty(htmlID, "ondragover")
 		}
 
 	case DragOverEvent:
 		if view.getRaw(DragOverEvent) != nil {
 			session.updateProperty(htmlID, "data-drag-over", "1")
 		} else {
-			session.removeProperty(view.htmlID(), "data-drag-over")
+			session.removeProperty(htmlID, "data-drag-over")
 		}
 
 	case DragData:
@@ -843,50 +848,66 @@ func (view *viewData) propertyChanged(tag PropertyName) {
 			session.updateProperty(htmlID, "data-drag", data)
 			session.updateProperty(htmlID, "ondragstart", "dragStartEvent(this, event)")
 		} else {
-			session.removeProperty(view.htmlID(), "draggable")
+			session.removeProperty(htmlID, "draggable")
-			session.removeProperty(view.htmlID(), "data-drag")
+			session.removeProperty(htmlID, "data-drag")
 			if view.getRaw(DragStartEvent) == nil {
-				session.removeProperty(view.htmlID(), "ondragstart")
+				session.removeProperty(htmlID, "ondragstart")
 			}
 		}
 
 	case DragImage:
-		if img, ok := stringProperty(view, DragImage, view.session); ok && img != "" {
+		if img, ok := stringProperty(view, DragImage, session); ok && img != "" {
 			img = strings.Trim(img, " \t")
 			if img[0] == '@' {
-				img, ok = view.session.ImageConstant(img[1:])
+				img, ok = session.ImageConstant(img[1:])
 				if !ok {
-					session.removeProperty(view.htmlID(), "data-drag-image")
+					session.removeProperty(htmlID, "data-drag-image")
 					return
 				}
 			}
 			session.updateProperty(htmlID, "data-drag-image", img)
 		} else {
-			session.removeProperty(view.htmlID(), "data-drag-image")
+			session.removeProperty(htmlID, "data-drag-image")
 		}
 
 	case DragImageXOffset:
 		if f := GetDragImageXOffset(view); f != 0 {
 			session.updateProperty(htmlID, "data-drag-image-x", f)
 		} else {
-			session.removeProperty(view.htmlID(), "data-drag-image-x")
+			session.removeProperty(htmlID, "data-drag-image-x")
 		}
 
 	case DragImageYOffset:
 		if f := GetDragImageXOffset(view); f != 0 {
 			session.updateProperty(htmlID, "data-drag-image-y", f)
 		} else {
-			session.removeProperty(view.htmlID(), "data-drag-image-y")
+			session.removeProperty(htmlID, "data-drag-image-y")
 		}
 
-	case DragEffect:
+	case DropEffect:
-		effects := enumProperties[DragEffect].cssValues
+		effect := GetDropEffect(view)
-		if n := GetDragEffect(view); n > 0 && n < len(effects) {
+		switch effect {
-			session.updateProperty(htmlID, "data-drag-effect", effects[n])
+		case DropEffectCopy:
+			session.updateProperty(htmlID, "data-drop-effect", "copy")
+		case DropEffectMove:
+			session.updateProperty(htmlID, "data-drop-effect", "move")
+		case DropEffectLink:
+			session.updateProperty(htmlID, "data-drop-effect", "link")
+		default:
+			session.removeProperty(htmlID, "data-drop-effect")
+		}
+
+	case DropEffectAllowed:
+		effect := GetDropEffectAllowed(view)
+		if effect >= DropEffectCopy && effect >= DropEffectAll {
+			values := []string{"undifined", "copy", "move", "copyMove", "link", "copyLink", "linkMove", "all"}
+			session.updateProperty(htmlID, "data-drop-effect-allowed", values[effect])
+		} else {
+			session.removeProperty(htmlID, "data-drop-effect-allowed")
 		}
 
 	case DataList:
-		updateInnerHTML(view.htmlID(), view.Session())
+		updateInnerHTML(htmlID, session)
 
 	case Opacity:
 		if f, ok := floatTextProperty(view, Opacity, session, 0); ok {