egert 缓动

//缓动开始和侦听完毕
var __tw2:egret.Tween = egret.Tween.get(target);
_tw2.to({scaleX:1,scaleY:1,alpha:1},1500,null);
_tw2.call(this.dragScaleOver,this);

//停止缓动
egret.Tween.pauseTweens(targetMc);
//targetMc.pause();
targetMc=null;