如何平穩地暫停動畫？

Question

我創造了一個命運之輪，但我無法阻止它。 如何平穩地停止用戶啟動的，手勢控制的圓形物體運動。 我能夠突然停止該對象，但希望有一個平穩的停止過程。

   let spinAnimation = CABasicAnimation()
   spinAnimation.fromValue = 0
    // goes to 360 ( 2 * π )
    spinAnimation.toValue = M_PI*2
    // define how long it will take to complete a 360
    spinAnimation.duration = 10
    // make it spin infinitely
    spinAnimation.repeatCount = Float.infinity
    // do not remove when completed
    spinAnimation.removedOnCompletion = false
    // specify the fill mode
    spinAnimation.fillMode = kCAFillModeForwards
    // and the animation acceleration
    spinAnimation.timingFunction = CAMediaTimingFunction(name:    kCAMediaTimingFunctionLinear)

    counterView.layer.backgroundColor = UIColor.redColor().CGColor

    // add the animation to the button layer
    counterView.layer.addAnimation(spinAnimation, forKey: "transform.rotation.z")

Answer 1

更改
spinAnimation.timingFunction = CAMediaTimingFunction(name: kCAMediaTimingFunctionLinear)

至
spinAnimation.timingFunction = CAMediaTimingFunction(name: kCAMediaTimingFunctionEaseOut)
隨着時間的流逝，緩和應該會減慢動畫的速度。 有關計時的詳細信息，請參見https://developer.apple.com/library/mac/documentation/Cocoa/Reference/CAMediaTimingFunction_class/#//apple_ref/doc/constant_group/Predefined_Timing_Functions