private onAddToStage(event:egret.Event) {

    RES.addEventListener(RES.ResourceEvent.GROUP_COMPLETE, this.onGroupComplete, this);
    RES.loadConfig("resource/default.res.json", "resource/");
    RES.loadGroup("preload");
}
private onGroupComplete()
{
      //this.drawText();
    var img:egret.Bitmap = new egret.Bitmap();
    img.texture = RES.getRes("egret_icon_png");
    this.addChild(img);
     img.touchEnabled = true;
    //注册事件
    img.addEventListener( egret.TouchEvent.TOUCH_TAP, this.onTouch, this );
}