动画缩放和移动UIView（快速）

Question

我有一个UIView，放在屏幕中间。当用户按下按钮时，我希望它向上移动靠近屏幕顶部，因为它缩小到大小的五分之一。

我试过这个：

UIView.animateWithDuration(0.7) { () -> Void in
            self.main.transform = CGAffineTransformMakeScale(0.2, 0.2)
            self.main.transform = CGAffineTransformMakeTranslation(0, -250)
        }

但出于某种原因，这只能缩放视图。我也尝试将它放在animateWithDuration中：

self.main.frame = CGRectMake(self.view.frame.width/2 - 10, 50, 50, 50)

如何让两种动画都能正常工作？

Answer 1

您可以在 Swift 中以多种方式实现基本UIView animation。下面的代码只是一个简单的方法......

class ViewController: UIViewController {

@IBOutlet weak var animationButton: UIButton!
@IBOutlet weak var myView: UIView!

override func viewDidLoad() {
    super.viewDidLoad()
    // I added seperate colour to UIView when animation move from one animation block to another.So, You can get better understanding how the sequence of animation works.
  self.myView.backgroundColor = .red
}

@IBAction func animateButton(_ sender: UIButton) {

    UIView.animate(withDuration: 0.5, delay: 0.0, options: UIViewAnimationOptions.curveEaseIn, animations: { 
        //Frame Option 1:
        self.myView.frame = CGRect(x: self.myView.frame.origin.x, y: 20, width: self.myView.frame.width, height: self.myView.frame.height)

        //Frame Option 2:
        //self.myView.center = CGPoint(x: self.view.frame.width / 2, y: self.view.frame.height / 4)
        self.myView.backgroundColor = .blue

        },completion: { finish in

    UIView.animate(withDuration: 1, delay: 0.25,options: UIViewAnimationOptions.curveEaseOut,animations: {
        self.myView.backgroundColor = .orange      
        self.myView.transform = CGAffineTransform(scaleX: 0.25, y: 0.25)

        self.animationButton.isEnabled = false // If you want to restrict the button not to repeat animation..You can enable by setting into true

        },completion: nil)})

      }
     } 

<强>输出：

Answer 2

Joe上面的回答与他的GIF描述完全相同，但它并没有真正回答你的问题，因为它翻译然后缩放视图（而不是同时进行翻译和缩放）。您的问题是您在动画块中设置视图的变换，然后立即用另一个变换覆盖该值。要同时实现翻译和扩展，你需要这样的东西：

@IBAction func animateButton(_ sender: UIButton) {
    let originalTransform = self.main.transform
    let scaledTransform = originalTransform.scaledBy(x: 0.2, y: 0.2)
    let scaledAndTranslatedTransform = scaledTransform.translatedBy(x: 0.0, y: -250.0)
    UIView.animate(withDuration: 0.7, animations: {
        self.main.transform = scaledAndTranslatedTransform
    })
}