键值编码在CABasicAnimation

Question

我目前正在尝试创建一个具有基于触摸功能的自定义UIControl。我的问题是，当我调用transform方法时，opacity和func setValue forKeyPath 键路径不会被分开，尽管图层动画完全不同。

简单来说：

1. touchesBegan和touchesEnded在opacity和（b）backgroundCircle图层上的{a} transform更改后应用了CATransform3DRotate } topLayer。
2. CALayer的扩展程序（a）通过addAnimation和（b）添加动画，并通过setValue设置keyPath的值，从而简化代码。

问题是不透明度不会动画回零，而是逐渐增加，直到完全不透明。但是，当我将keyPath更改为transform以外的任何内容时，它再次有效但是它不会为topLayer 设置动画。我不确定这里究竟是什么错误，但我怀疑它与keyPaths有关。

以下是方法和扩展：

1. backgroundCircle相关功能：

   func animateCircleToTransparent(completion:()->()) {
   
   let drawAnimation = CABasicAnimation(keyPath: "opacity")
   drawAnimation.duration = 0.2
   drawAnimation.repeatCount = 1
   drawAnimation.fromValue = backgroundCircleOpacity
   drawAnimation.toValue = 0
   drawAnimation.fillMode = kCAFillModeBackwards
   drawAnimation.autoreverses = false
   drawAnimation.timingFunction = CAMediaTimingFunction(controlPoints: 0.34, 0.01, 0.69, 1.37)
   self.backgroundCircle.ocb_applyAnimation(drawAnimation)
   
   }
   
   func animateCircleToOpaque(completion:()->()) {
   
   let drawAnimation = CABasicAnimation(keyPath: "opacity")
   drawAnimation.duration = 0.2
   drawAnimation.repeatCount = 1
   drawAnimation.fromValue = 0
   drawAnimation.toValue = backgroundCircleOpacity
   drawAnimation.fillMode = kCAFillModeBackwards
   drawAnimation.autoreverses = false
   drawAnimation.timingFunction = CAMediaTimingFunction(controlPoints: 0.34, 0.01, 0.69, 1.37)
   self.backgroundCircle.ocb_applyAnimation(drawAnimation)
   }
   

2. topLayer相关功能：

   func animateTopLineOn() {
   
   let topTransform = CABasicAnimation(keyPath: "transform")
   topTransform.timingFunction = CAMediaTimingFunction(controlPoints: 0.5, -0.8, 0.5, 1.85)
   topTransform.duration = 0.4
   topTransform.fillMode = kCAFillModeBackwards
   
   let translation = CATransform3DMakeTranslation(-4, 0, 0)
   topTransform.toValue = NSValue(CATransform3D: CATransform3DRotate(translation, -0.7853975, 0, 0, 1))
   topTransform.beginTime = CACurrentMediaTime() + 0.25
   
   self.topLayer.ocb_applyAnimation(topTransform)
   }
   
   
   func animateTopLineOff() {
   
   
   let topTransform = CABasicAnimation(keyPath: "transform")
   topTransform.timingFunction = CAMediaTimingFunction(controlPoints: 0.5, -0.8, 0.5, 1.85)
   topTransform.duration = 0.4
   topTransform.fillMode = kCAFillModeBackwards
   
   let translation = CATransform3DMakeTranslation(4, 0, 0)
   topTransform.toValue = NSValue(CATransform3D: CATransform3DRotate(translation, 0.7853975, 0, 0, 1))
   topTransform.beginTime = CACurrentMediaTime() + 0.25
   
   self.topLayer.ocb_applyAnimation(topTransform)
   }
   

3. ＆＃39;的CALayer＆＃39;扩展：

   extension CALayer {
   func ocb_applyAnimation(animation: CABasicAnimation) {
   let copy = animation.copy() as! CABasicAnimation
   
   if copy.fromValue == nil {
       copy.fromValue = self.presentationLayer()!.valueForKeyPath(copy.keyPath!)
   }
   
   self.addAnimation(copy, forKey: copy.keyPath!)
   self.setValue(copy.toValue, forKeyPath:copy.keyPath!)
   }
   }