通过sprite创建一个text样式的按钮

public static function createTextButton(text:String, tf:Object, para:*, instance:Object, func:Function):Sprite{
var btnSprite:Sprite = new Sprite();
var btnText:Text = new Text(text, tf);
btnText.autoSize = TextFieldAutoSize.LEFT;

btnText.selectable = false;
btnSprite.addChild(btnText);
btnSprite.buttonMode=true;
btnSprite.mouseChildren = false;

if(para == null) {
btnSprite.addEventListener(MouseEvent.CLICK, Func.bindAsEvent(instance,func));
} else {
btnSprite.addEventListener(MouseEvent.CLICK, Func.bindAsEvent(instance,func,para));
}

return btnSprite;
}