在动画Swift中淡入并淡出

Question

我有一个带有动画的UIImageView,在UIView中,我应用了一个fadeIn效果,但我需要在触摸时动画的UIImageView应用淡出.

这就是我为淡入而做的.

UIView.animateWithDuration(0.5, delay: delay, 
    options: UIViewAnimationOptions.CurveEaseOut, animations: {
        uiImageView.alpha = 1.0
        }

Answer 1

这是我根据我的研究做的事情:(假设你正在使用故事板)

1. 转到UIImageView,在Attributes下,选中"User Interaction Enabled"复选框.

2. 将TapGestureRecognizer拖动到图像视图的顶部.

3. 控制单击Tap Gesture并拖动以对ViewControler.swift进行操作.

4. 在里面添加以下代码:

   UIView.animate(withDuration: 0.5, delay: 0.5, options: .curveEaseOut, animations: {
       self.uiImageView.alpha = 0.0
   }, completion: nil) 
   

那你就完成了!

Answer 2

从iOS 10开始,Apple推出了新的iOS动画SDK,它功能更强大,特别是在时序功能和交互性方面.

使用这种方法淡出代码将:

UIViewPropertyAnimator(duration: 0.5, curve: .easeOut, animations: {
    self.uiImageView.alpha = 0.0
}).startAnimation()

要获得有关Property Animator的更多详细信息,请查看iOS 10 Animations演示.

Answer 3

斯威夫特4.向UIView对象添加淡入和淡出功能

extension UIView {

    func fadeIn(_ duration: TimeInterval = 0.5, delay: TimeInterval = 0.0, completion: @escaping ((Bool) -> Void) = {(finished: Bool) -> Void in}) {
        UIView.animate(withDuration: duration, delay: delay, options: UIViewAnimationOptions.curveEaseIn, animations: {
            self.alpha = 1.0
    }, completion: completion)  }

    func fadeOut(_ duration: TimeInterval = 0.5, delay: TimeInterval = 1.0, completion: @escaping (Bool) -> Void = {(finished: Bool) -> Void in}) {
        UIView.animate(withDuration: duration, delay: delay, options: UIViewAnimationOptions.curveEaseIn, animations: {
            self.alpha = 0.3
    }, completion: completion)
   }
}

例

label.fadeIn()

label.fadeOut()

imageView.fadeOut(completion: {
    (finished: Bool) -> Void in
    imageView.removeFromSuperview()
})

label.fadeIn(completion: {
    (finished: Bool) -> Void in
    label.text = "Changed!"
})