我有一个简单的应用程序,它是 red
View 变换位置从左屏幕到右屏幕。我希望当我点击 remove
按钮时,动画将重新启动(red
View 变换位置再次从左屏幕到右屏幕)但它不起作用。 red
View 回到原始帧,但它没有移动,但 animationDidStop
仍然在持续时间后调用。
class TestViewController: UIViewController, CAAnimationDelegate {
let testView : UIView = {
let view = UIView()
view.translatesAutoresizingMaskIntoConstraints = false
view.backgroundColor = .red
view.layer.borderColor = UIColor.black.cgColor
view.layer.cornerRadius = 5
return view
}()
let removeAniButton : UIButton = {
let btn = UIButton(type: .system)
btn.translatesAutoresizingMaskIntoConstraints = false
btn.setTitle("Remove", for: .normal)
return btn
}()
let addAniButton : UIButton = {
let btn = UIButton(type: .system)
btn.translatesAutoresizingMaskIntoConstraints = false
btn.setTitle("Add", for: .normal)
return btn
}()
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = .white
view.addSubview(testView)
testView.leftAnchor.constraint(equalTo: self.view.leftAnchor).isActive = true
testView.centerYAnchor.constraint(equalTo: self.view.centerYAnchor).isActive = true
testView.heightAnchor.constraint(equalToConstant: 100).isActive = true
testView.widthAnchor.constraint(equalToConstant: 100).isActive = true
view.addSubview(removeAniButton)
removeAniButton.topAnchor.constraint(equalTo: self.view.topAnchor, constant: 50).isActive = true
removeAniButton.centerXAnchor.constraint(equalTo: self.view.centerXAnchor).isActive = true
removeAniButton.widthAnchor.constraint(equalToConstant: 100).isActive = true
removeAniButton.heightAnchor.constraint(equalToConstant: 50).isActive = true
removeAniButton.addTarget(self, action: #selector(removeAnimation), for: .touchUpInside)
view.addSubview(addAniButton)
addAniButton.topAnchor.constraint(equalTo: self.view.topAnchor, constant: 150).isActive = true
addAniButton.centerXAnchor.constraint(equalTo: self.view.centerXAnchor).isActive = true
addAniButton.widthAnchor.constraint(equalToConstant: 100).isActive = true
addAniButton.heightAnchor.constraint(equalToConstant: 50).isActive = true
addAniButton.addTarget(self, action: #selector(addAnimation), for: .touchUpInside)
addAnimation()
// Do any additional setup after loading the view.
}
func createAnimation() -> CAAnimation {
let animation = CABasicAnimation(keyPath: "position.x")
animation.fromValue = 0
animation.toValue = self.view.frame.width
animation.duration = 4
animation.timingFunction = CAMediaTimingFunction.init(name: kCAMediaTimingFunctionLinear)
animation.fillMode = kCAFillModeForwards
animation.isRemovedOnCompletion = false
animation.delegate = self
return animation
}
func removeAnimation(){
testView.layer.removeAllAnimations()
testView.transform = .identity
addAnimation()
}
func addAnimation(){
testView.layer.add(createAnimation(), forKey: nil)
}
func animationDidStop(_ anim: CAAnimation, finished flag: Bool) {
if flag {
print("Animation is finished")
}
}
}
谁能解释一下?
最佳答案
您的问题是您为动画使用了错误的 keyPath,如果您想使用 testView.transform = .identity
重置动画,您需要使用 transform.translation.x
而不是“position.x”作为动画 keyPath,也不需要调用 removeAllAnimations()
只需再次调用您的 addAnimation
即可完成工作
使用此代码创建动画
func createAnimation() -> CAAnimation {
let animation = CABasicAnimation(keyPath: "transform.translation.x")
animation.fromValue = 0
animation.toValue = self.view.frame.width
animation.duration = 4
animation.timingFunction = CAMediaTimingFunction.init(name: kCAMediaTimingFunctionLinear)
animation.fillMode = kCAFillModeForwards
animation.isRemovedOnCompletion = false
return animation
}
func removeAnimation(){
//customView.layer.removeAllAnimations()
//customView.transform = .identity
addAnimation()
}
关于ios - removeAllAnimations 不起作用后添加动画,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/45939131/