Flex: Drag and drop, simple example - apache-flex

Question

I want to implement drag&drop possibilities in my application. Here is my source code:
I added images to the container, and now want to be able to move them from element PieceContainer to element board (defined in the another class). I tried to define mouse move handler as it was shown here: http://livedocs.adobe.com/flex/3/html/help.html?content=dragdrop_7.html, but it doesn't do anything... Actually I don't understand how should I define drap initiator, and drop handler
public class PieceContainer extends Canvas
{
//private var image:Image = new Image();
private var piecesWhite:Dictionary;
private var piecesBlack:Dictionary;
private var images:ArrayCollection = new ArrayCollection();
private var placeX:Number;
public var items:Dictionary;
public function PieceContainer()
{
super();
this.addEventListener(Event.ADDED_TO_STAGE, displayPiece);
}
private function displayPiece(event:Event):void
{
placePiecesDict(new Point(0, 0), items);
}
private function placePiecesDict(start:Point, dict:Dictionary):void
{
placeX = 0;
for (var item:* in dict)
{
var image:Image = new Image();
image.source = dict[item];
image.x = placeX/1.4;
image.y = start.y;
image.addEventListener(MouseEvent.MOUSE_MOVE, doDrag);
images.addItem(image);
this.addChild(image);
placeX += height;
}
}
private function doDrag(evt:Event):void
{
trace(evt);
}
}
Please also see attached image for some more description:
http://img.skitch.com/20091221-e6j8d62y9iin621hmcdbssrp6d.png
I reorganized code this way:
public class PieceContainer extends Canvas
{
private var piecesWhite:Dictionary;
private var piecesBlack:Dictionary;
private var images:ArrayCollection = new ArrayCollection();
private var placeX:Number;
public var items:Dictionary;
public function PieceContainer()
{
super();
this.addEventListener(Event.ADDED_TO_STAGE, displayPiece);
}
private function displayPiece(event:Event):void
{
placePiecesDict(new Point(0, 0), items);
}
private function placePiecesDict(start:Point, dict:Dictionary):void
{
placeX = 0;
for (var item:* in dict)
{
var image:Image = new Image();
image.source = dict[item];
image.x = placeX/1.4;
image.y = start.y;
image.addEventListener(MouseEvent.MOUSE_MOVE, mouseMoveHandler);
images.addItem(image);
this.addChild(image);
placeX += height;
}
}
private function mouseMoveHandler(evt:MouseEvent):void
{
var dragInitiator:Image = Image(evt.currentTarget);
var ds:DragSource = new DragSource();
ds.addData(dragInitiator, "img");
DragManager.doDrag(dragInitiator, ds, evt);
}
And also added drag and drop handlers to the board:
public class BoardCell extends Canvas
{
private var _color:Number;
public function BoardCell()
{
super();
this.addEventListener(DragEvent.DRAG_ENTER, dragEnterHanler);
this.addEventListener(DragEvent.DRAG_DROP, dragDropHandler);
}
public function placeMe(x:int, y:int, width:Number, color:Number):void
{
graphics.lineStyle(1, 0x000000);
graphics.beginFill(color);
graphics.drawRect(x, y, width, width);
graphics.endFill();
}
private function dragEnterHanler(event:DragEvent):void
{
if(event.dragSource.hasFormat("img"))
{
DragManager.acceptDragDrop(Canvas(event.currentTarget))
}
}
private function dragDropHandler(event:DragEvent):void
{
event.dragInitiator.x = 0;
event.dragInitiator.y = 0;
}
But actually have 2 problems:
First: Items are draggable, but when i add them to board they stays on in the PiecesContainer.
Second: I want items to be copied, rather then just moved (but when they are on board they should be movable, not copied)
Thanks, in advance

Answer 1

First problem is easily fixed. dragMoveEnabled=true is how you do it in a list control, but since your doing something very custom you will want to look back at the drag initiator and delete the drug item from it. Details here:
http://livedocs.adobe.com/flex/3/html/help.html?content=dragdrop_8.html
This will also help you set up your drag and drop functions so you can solve problem 2 as well.