Question

我有从UIScrollView继承的自定义类，其中包含“关闭按钮”视图。按“关闭按钮”，我想进行动画缩放转换，然后从SuperView中删除整个视图。

class AddReview : UIScrollView { 

override init(frame: CGRect){
    super.init(frame: frame)

    let closeButton = CloseButtonView()
    closeButton.frame = CGRect(x:frame.maxX - 50, y:0, width: 50, height: 50)
    self.addSubview(closeButton)

    let tapCloseGestureRecognizer = UITapGestureRecognizer(target:self, action:#selector(closeButtonPressed))
    closeButton.isUserInteractionEnabled = true
    closeButton.addGestureRecognizer(tapCloseGestureRecognizer)
}

func closeButtonPressed(){
    UIView.animate(withDuration: 0.3){
       self.transform = CGAffineTransform(scaleX: 1.1, y: 1.1)
    }

    UIView.animate(withDuration: 0.2, delay: 0.4, animations: { () -> Void in
       self.transform = CGAffineTransform(scaleX: 0.1, y: 0.1)
    }, completion: { (finished: Bool) -> Void in
        if (finished)
        {
            //self.removeFromSuperview()
        }
    })
}

required init?(coder aDecoder: NSCoder) {
    fatalError("init(coder:) has not been implemented")
}

}

我的问题是没有动画发生。视图会立即被删除，或者当removeFromSuperview被注释掉时，它会被调整为10％而没有动画。

我尝试过使用layoutIfNeeded，主要队列的调度以及其他很多东西，但是没有工作。

更重要的是，我注意到它有时会起作用，但大部分时间都不起作用！

知道可能有什么问题吗？非常感谢任何建议：）

Answer 1

正如Magnas所说，第二个动画在第一个动画有机会完成之前被调用。尝试：

UIView.animate(withDuration: 0.3, animations: { () -> Void in
    self.transform = CGAffineTransform(scaleX: 1.1, y: 1.1)
}, completion: { (finished: Bool) -> Void in
    // wait for first animation to complete
    UIView.animate(withDuration: 0.2, animations: { () -> Void in
        self.transform = CGAffineTransform(scaleX: 0.1, y: 0.1)
    }, completion: { (finished: Bool) -> Void in
        if (finished)
        {
            //self.removeFromSuperview()
        }
    })
})

这可以略微缩短：

UIView.animate(withDuration: 0.3, animations: {
    self.transform = CGAffineTransform(scaleX: 1.1, y: 1.1)
}, completion: { (finished: Bool) -> Void in
    // wait for first animation to complete
    UIView.animate(withDuration: 0.2, animations: {
        self.transform = CGAffineTransform(scaleX: 0.1, y: 0.1)
    }, completion: { finished in
        if (finished)
        {
            //self.removeFromSuperview()
        }
    })
})

swift UIView.animate跳过动画

1 个答案: