Swift连续旋转动画不是那么连续

Question

这是我的代码.意图是连续旋转名为swirls [l]的UIImageView.但是,每个旋转开始/结束之间会有一个小的暂停.我已经完成了每一个动画教程,但无法弄清楚错误是什么？

let fullRotation = CGFloat(M_PI * 2)

    let duration = 2.0
    let delay = 0.0
    let options = UIViewKeyframeAnimationOptions.Repeat | UIViewKeyframeAnimationOptions.CalculationModeLinear

    UIView.animateKeyframesWithDuration(duration, delay: delay, options: options, animations: {
        UIView.addKeyframeWithRelativeStartTime(0, relativeDuration: 1/3, animations: {
            swirls[l].transform = CGAffineTransformMakeRotation(1/3 * fullRotation)
        })
        UIView.addKeyframeWithRelativeStartTime(1/3, relativeDuration: 1/3, animations: {
            swirls[l].transform = CGAffineTransformMakeRotation(2/3 * fullRotation)
        })
        UIView.addKeyframeWithRelativeStartTime(2/3, relativeDuration: 1/3, animations: {
            swirls[l].transform = CGAffineTransformMakeRotation(3/3 * fullRotation)
        })

        }, completion: {finished in 
    })

编辑:我看到有人建议先前的解决方案可用,但它不能用于连续不间断的旋转.对我有用的唯一技巧是我在下面选择的答案.谢谢

Answer 1

尝试以下扩展名为swift 4.

extension UIView {
    func rotate360Degrees(duration: CFTimeInterval = 3) {
        let rotateAnimation = CABasicAnimation(keyPath: "transform.rotation")
        rotateAnimation.fromValue = 0.0
        rotateAnimation.toValue = CGFloat(Double.pi * 2)
        rotateAnimation.isRemovedOnCompletion = false
        rotateAnimation.duration = duration
        rotateAnimation.repeatCount=Float.infinity
        self.layer.add(rotateAnimation, forKey: nil)
    }
}

开始旋转.

MyView.rotate360Degrees()

而对于停止.

MyView.layer.removeAllAnimations()

您可以使用UIButton,UILabel等等.

Answer 2

我不确定你的代码有什么问题,但我用这种方法实现了连续旋转,

@IBAction func rotateView(sender: UIButton) {
    UIView.animate(withDuration: 0.5, delay: 0, options: .curveLinear, animations: { () -> Void in
        self.spinningView.transform = self.spinningView.transform.rotated(by: .pi / 2)
    }) { (finished) -> Void in
        self.rotateView(sender: sender)
    }
}

Answer 3

如果你想连续旋转按钮或查看并随时停止旋转,那么你可以试试这个:开始旋转:

@IBOutlet weak var RotateBtn: UIButton!
var timeTimer: Timer?

viewDidLoad()
{
  self.rotateView()
  timeTimer = Timer.scheduledTimer(timeInterval: 0.5, target: self, selector: #selector(self.rotateView), userInfo: nil, repeats: true)
}

func rotateView()
{
    UIView.animate(withDuration: 0.5, delay: 0, options: .curveLinear, animations: { () -> Void in
        self.RotateBtn.transform = self.RotateBtn.transform.rotated(by: CGFloat(M_PI_4))
    })
}

如果要停止旋转,请使用:

@IBAction func StopBtn_Pressed(_ sender: AnyObject)
{
   timeTimer?.invalidate()
   self.RecordBtn.layer.removeAllAnimations()
}