ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Drag and drop in AIR
Starting a drag-out operation
Adobe AIR 1.0 and later
To start a drag operation, call the NativeDragManager.doDrag() method in response to a mouse down event. The
doDrag() method is a static method that takes the following parameters:
Parameter Description
initiator The object from which the drag originates, and which dispatches the dragStart and dragComplete
events. The initiator must be an interactive object.
clipboard The Clipboard object containing the data to be transferred. The Clipboard object is referenced in the
NativeDragEvent objects dispatched during the drag-and-drop sequence.
dragImage (Optional) A BitmapData object to display during the drag. The image can specify an alpha value. (Note:
Microsoft Windows always applies a fixed alpha fade to drag images).
offset (Optional) A Point object specifying the offset of the drag image from the mouse hotspot. Use negative
coordinates to move the drag image up and left relative to the mouse cursor. If no offset is provided, the top,
left corner of the drag image is positioned at the mouse hotspot.
actionsAllowed (Optional) A NativeDragOptions object specifying which actions (copy, move, or link) are valid for the drag
operation. If no argument is provided, all actions are permitted. The DragOptions object is referenced in
NativeDragEvent objects to enable a potential drag target to check that the allowed actions are compatible
with the purpose of the target component. For example, a “trash” component might only accept drag
gestures that allow the move action.
The following example illustrates how to start a drag operation for a bitmap object loaded from a file. The example
loads an image and, on a mouseDown event, starts the drag operation.
package
{
import flash.desktop.NativeDragManager;
import mx.core.UIComponent;
import flash.display.Sprite;
import flash.display.Loader;
import flash.system.LoaderContext;
import flash.net.URLRequest;
import flash.geom.Point;
import flash.desktop.Clipboard;
import flash.display.Bitmap;
import flash.filesystem.File;
import flash.events.Event;
import flash.events.MouseEvent;
public class DragOutExample extends UIComponent Sprite {
protected var fileURL:String = "app:/image.jpg";
protected var display:Bitmap;
private function init():void {
loadImage();
}
private function onMouseDown(event:MouseEvent):void {
var bitmapFile:File = new File(fileURL);
var transferObject:Clipboard = createClipboard(display, bitmapFile);
NativeDragManager.doDrag(this,
transferObject,
display.bitmapData,
Last updated 6/6/2012
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