拖动元件延时跟随的动画效果

/**
 * 实现拖动延时效果的代码
 */

package {
	import fl.transitions.Tween;
	import fl.transitions.TweenEvent;
	import fl.transitions.easing.Strong;

	import flash.display.Sprite;
	import flash.display.StageAlign;
	import flash.display.StageScaleMode;
	import flash.events.MouseEvent;
	import flash.events.TimerEvent;
	import flash.utils.Timer;

	public class DragEffect extends Sprite
	{
		private var regularTweenX:Tween;
		private var regularTweenY:Tween;
		private var noneTweenX:Tween;
		private var noneTweenY:Tween;

		private var goalX:Number;
		private var goalY:Number;

		[Embed(source="com/gde/assets/light.swf", symbol="Light")]
		private var Light :Class;

		private var light:*;

		private var timer:Timer;

		public function DragEffect()
		{
			//设置flash在网页缩放的时候，不缩放内部元件，而可以裁切显示内容
			stage.scaleMode = StageScaleMode.NO_SCALE;
			stage.align = StageAlign.TOP_LEFT;

			timer = new Timer(3);
			timer.addEventListener(TimerEvent.TIMER, easeMoveHandler);

			light = new Light();
			light.x = 0;
			light.y = 0;
			this.addChild(light);
			stage.addEventListener(MouseEvent.MOUSE_MOVE, moveHandler);
		}

		private function moveHandler(e:MouseEvent):void{
			goalX = e.stageX;
			goalY = e.stageY;
			timer.reset();
			timer.start();
		}

		private function easeMoveHandler(e:TimerEvent):void{
			if(regularTweenY != null){
				regularTweenY.stop();
			}
			regularTweenY = new Tween(light, "x", Strong.easeOut, light.x, goalX, Math.abs(goalX - light.x)/500, true);
		}

	}
}