CABasicAnimation 链接不起作用

Question

我在链接多个 CABasicAnimation 时遇到困难。我只想将按钮缩放到其大小的 1.5 倍，然后缩放到 0.5 并逐渐消失（同时缩小）。

问题是只有放大才能起作用，然后按钮会返回到原始状态。

我会使用 CGAffineTransformMakeScale 但它在 iOS 7 中产生了一个错误。在 iOS 8 和 9 上它工作正常

我尝试使用 CAAnimationGroup 但结果相同。

代码如下：

    let scaleUp = CABasicAnimation(keyPath: "transform.scale")
    scaleUp.fromValue = 1
    scaleUp.toValue = 1.5
    scaleUp.duration = 0.2
    scaleUp.beginTime = 0
    scaleUp.removedOnCompletion = true
    self.myButton.layer.addAnimation(scaleUp, forKey: "up")

    let scaleDown = CABasicAnimation(keyPath: "transform.scale")
    scaleDown.fromValue = 1
    scaleDown.toValue = 0.5
    scaleDown.duration = 0.2
    scaleDown.beginTime = scaleUp.beginTime + scaleDown.duration
    scaleDown.removedOnCompletion = true
    self.myButton.layer.addAnimation(scaleDown, forKey: "down")

    let fade = CABasicAnimation(keyPath: "opacity")
    fade.fromValue = 1
    fade.toValue = 0
    fade.duration = 0.2
    fade.beginTime = scaleUp.beginTime + scaleDown.duration
    fade.removedOnCompletion = false
    self.myButton.layer.addAnimation(fade, forKey: "fade")

Answer 1

这对我来说非常有用，可以随意调整持续时间或其他动画属性。

我尝试使用您的动画说明，但这并不意味着我已经根据您的期望正确设置了所有属性。

Swift (2.x)

func addGrowShrinkAndFadeOutAnimationToView(viewToAnimate: UIView) {

    let easeInOutTiming = CAMediaTimingFunction(name: kCAMediaTimingFunctionEaseInEaseOut)

    let viewScaleXAnimation = CAKeyframeAnimation(keyPath: "transform.scale.x")
    viewScaleXAnimation.duration = 0.4
    viewScaleXAnimation.values = [1.0 as Float, 1.5 as Float, 0.5 as Float]
    viewScaleXAnimation.keyTimes = [0.0 as Float, 0.5 as Float, 1.0 as Float]
    viewScaleXAnimation.timingFunctions = [easeInOutTiming, easeInOutTiming]
    viewToAnimate.layer.addAnimation(viewScaleXAnimation, forKey:"Grow, Shrink and Fade out_ScaleX")

    let viewScaleYAnimation = CAKeyframeAnimation(keyPath: "transform.scale.y")
    viewScaleYAnimation.duration = 0.4
    viewScaleYAnimation.values = [1.0 as Float, 1.5 as Float, 0.5 as Float]
    viewScaleYAnimation.keyTimes = [0.0 as Float, 0.5 as Float, 1.0 as Float]
    viewScaleYAnimation.timingFunctions = [easeInOutTiming, easeInOutTiming]
    viewToAnimate.layer.addAnimation(viewScaleYAnimation, forKey:"Grow, Shrink and Fade out_ScaleY")

    let viewOpacityAnimation = CAKeyframeAnimation(keyPath: "opacity")
    viewOpacityAnimation.duration = 0.4
    viewOpacityAnimation.values = [1.0 as Float, 1.0 as Float, 0.0 as Float]
    viewOpacityAnimation.keyTimes = [0.0 as Float, 0.5 as Float, 1.0 as Float]
    viewOpacityAnimation.timingFunctions = [easeInOutTiming, easeInOutTiming]
    viewToAnimate.layer.addAnimation(viewOpacityAnimation, forKey:"Grow, Shrink and Fade out_Opacity")

}

Answer 2

您想使用 CA 动画有什么具体原因吗？我发现操纵约束更容易。我在情节提要中添加了一个按钮，并为按钮的高度和宽度约束创建了插座。

@IBOutlet weak var okButton: UIButton!
@IBOutlet weak var widthConstraint: NSLayoutConstraint!
@IBOutlet weak var heightConstraint: NSLayoutConstraint!
var buttonWidth : CGFloat?
var buttonHeight : CGFloat?

override func viewDidLoad() {
    super.viewDidLoad()
    self.buttonHeight = self.heightConstraint.constant
    self.buttonWidth = self.widthConstraint.constant
}

@IBAction func okButtonTapped(button: UIButton) {
    let animationDuration = 2.0
    self.heightConstraint.constant = self.buttonWidth! * 2.0
    self.widthConstraint.constant = self.buttonHeight! * 2.0
    UIView.animateWithDuration(animationDuration, animations: {
       button.layoutIfNeeded()
    }) { (finished) in
            self.heightConstraint.constant = self.buttonWidth! * 0.5
            self.widthConstraint.constant = self.buttonHeight! * 0.5
            UIView.animateWithDuration(animationDuration, animations: {
                button.alpha = 0.0
                button.layoutIfNeeded()
                }, completion: { (finished) in
                   button.hidden = true
            })
    }
}

CABasicAnimation 链接不起作用

CABasicAnimation chaining not working

cabasicanimation

swift

Swift (2.x)