如何在 Swift 3.0 中使用动画创建时间延迟

Question

1. 首先我们生成一个随机数（例如从 0 到 10）：

   If randomNumber = 0
       Animate imageSet0 [here we create an ImageArray and an animate function – please see code below)
   Else if randomNumber = 1
       Animate imageSet1
   Else if randomNumber = 2
       Animate imageSet2
   And so on…
   

2. 然后我们放置一个DispatchQueue定时器，等待上述动画完成（延时等于animationDuration），然后我们重复上面的第一步，生成另一个随机数，播放另一个动画集：

   DispatchQueue.main.asyncAfter(deadline: .now() + imageView.animationDuration) {
      [Insert code that repeats the first step above and generates another random number to play another animation set]
   }
   

3. 理论上，这个随机动画可以无限期地播放，直到用户移过这个场景。

到目前为止，这是我的代码：

func createImageArray(total: Int, imagePrefix: String) -> [UIImage]{
    var imageArray: [UIImage] = []
    for imageCount in 0..<total {
        let imageName = "\(imagePrefix)-\(imageCount).png"
        let image = UIImage(named: imageName)!

        imageArray.append(image)
    }

    return imageArray

}


func animate(imageView: UIImageView, images: [UIImage]){
    imageView.animationImages = images
    imageView.animationDuration = 1.0
    imageView.animationRepeatCount = 1
    imageView.startAnimating()

    DispatchQueue.main.asyncAfter(deadline: .now() + imageView.animationDuration) {

[Create code that repeats the first step above and generates another random number to play another animation set]

    }
}

Answer 1

您可以为此使用UIView.animate(withDuration: delay: options: animations:) api。注意延迟参数会让你在一定的延迟后开始动画。