Swift动画重复次数

Question

我有下面的代码想淡入淡出一个UILabel。但我只想让它重复淡入淡出5次。我的问题是如何设置动画只重复3次？

func savingIcon(){
    Loading.hidden=false
    UIView.animateWithDuration(1.0,
                               delay: 0.0,
                               options: [ .CurveEaseInOut],
                               animations: {

                                self.Loading.alpha=0.0;
                                self.Loading.alpha=1.0;
                                self.Loading.alpha=0.0;
                                self.Loading.alpha=1.0;
                                self.Loading.alpha=0.0;

        },
                               completion: { finished in
                                print("Save done")

                                self.Loading.hidden=true


    })

}