动画按钮导致按钮无法工作

Question

我决定在没有填写某些细节时尝试设置按钮动画。但是，当按钮动画时，它变得不可操作。有人可以解释为什么会这样吗？

这是我的代码：

override func viewDidLoad() {
    super.viewDidLoad()     
    EnterDet.alpha = 1
    animateText()
}

func animateText(){
    UIView.animate(withDuration: 1.0, animations: {
        self.EnterDet.alpha = 1
    }, completion:  {
        (Comnpleted : Bool) -> Void in

        UIView.animate(withDuration: 1.0, delay: 3.0, options: UIViewAnimationOptions.curveLinear, animations: {
        self.EnterDet.alpha = 0.1

        }, completion: {
            (Completed : Bool) -> Void in
            self.animateText()
        })
    })
}