I am able to drag a copy of an object and drop it on the canvas, using drag-drop manager functi开发者_如何学Conality in Flex.
The original object remains unchanged and a new copy of the object is created. However, If i further want to drag this copy and position it differently on the canvas, I find that the object is not draggable.
Since this copy is created at runtime, I am not sure how I can achieve to drag it?
My code is given below.
Any suggestions will help.
<mx:Script>
<![CDATA[
import mx.managers.DragManager;
import mx.core.DragSource;
import mx.events.DragEvent;
import flash.events.MouseEvent;
// Embed icon image.
[Embed(source='car.png')]
public var globeImage:Class;
// The mouseMove event handler for the Image control
// functioning as the drag initiator.
private function mouseOverHandler(event:MouseEvent):void
{
var dragInitiator:Image=Image(event.currentTarget);
var ds:DragSource = new DragSource();
ds.addData(dragInitiator, "img");
// The drag manager uses the image as the drag proxy
// and sets the alpha to 1.0 (opaque),
// so it appears to be dragged across the canvas.
var imageProxy:Image = new Image();
imageProxy.source = globeImage;
imageProxy.height=10;
imageProxy.width=10;
DragManager.doDrag(dragInitiator, ds, event,
imageProxy, -15, -15, 1.00);
}
// The dragEnter event handler for the Canvas container
// functioning as the drop target.
private function dragEnterHandler(event:DragEvent):void {
if (event.dragSource.hasFormat("img"))
DragManager.acceptDragDrop(Canvas(event.currentTarget));
}
// The dragOver event handler for the Canvas container
// sets the type of drag-and-drop
// operation as either copy or move.
// This information is then used in the
// dragComplete event handler for the source Canvas container.
private function dragOverHandler(event:DragEvent):void
{
DragManager.showFeedback(DragManager.COPY);
}
// The dragDrop event handler for the Canvas container
// sets the Image control's position by
// "dropping" it in its new location.
private function dragDropHandler(event:DragEvent):void {
if (event.dragSource.hasFormat("img")) {
var draggedImage:Image =
event.dragSource.dataForFormat('img') as Image;
var dropCanvas:Canvas = event.currentTarget as Canvas;
// Since this is a copy, create a new object to
// add to the drop target.
var newImage:Image=new Image();
newImage.source = draggedImage.source;
newImage.x = dropCanvas.mouseX;
newImage.y = dropCanvas.mouseY;
dropCanvas.addChild(newImage);
}
}
// The dragComplete event handler for the source Canvas container
// determines if this was a copy or move.
// If a move, remove the dragged image from the Canvas.
private function dragCompleteHandler(event:DragEvent):void {
var draggedImage:Image =
event.dragInitiator as Image;
var dragInitCanvas:Canvas =
event.dragInitiator.parent as Canvas;
if (event.action == DragManager.MOVE)
dragInitCanvas.removeChild(draggedImage);
}
]]>
</mx:Script>
<!-- Canvas holding the Image control that is the drag initiator. -->
<mx:Canvas
width="250" height="500"
borderStyle="solid"
backgroundColor="#DDDDDD">
<!-- The Image control is the drag initiator and the drag proxy. -->
<mx:Image id="myimg"
source="@Embed(source='car.png')"
mouseMove="mouseOverHandler(event);"
dragComplete="dragCompleteHandler(event);"/>
</mx:Canvas>
<!-- This Canvas is the drop target. -->
<mx:Canvas
width="250" height="500"
borderStyle="solid"
backgroundColor="#DDDDDD"
dragEnter="dragEnterHandler(event);"
dragOver="dragOverHandler(event);"
dragDrop="dragDropHandler(event);">
</mx:Canvas>
Change the dragDropHandler
method to:
private function dragDropHandler(event:DragEvent):void {
if (event.dragSource.hasFormat("img")) {
var draggedImage:Image =
event.dragSource.dataForFormat('img') as Image;
var dropCanvas:Canvas = event.currentTarget as Canvas;
// Since this is a copy, create a new object to
// add to the drop target.
var newImage:Image=new Image();
newImage.source = draggedImage.source;
newImage.x = dropCanvas.mouseX;
newImage.y = dropCanvas.mouseY;
newImage.addEventListener(MouseEvent.MOUSE_MOVE, mouseOverHandler);
newImage.addEventListener(DragEvent.DRAG_COMPLETE, dragCompleteHandler);
dropCanvas.addChild(newImage);
}
}
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