UIView无限360度旋转动画?

我试图旋转一个UIImageView 360度，并在网上看了几个教程。我不能让它们都工作，UIView要么停止，要么跳转到一个新位置。

我怎样才能做到这一点呢?

我最近尝试的是:

[UIView animateWithDuration:1.0
                      delay:0.0
                    options:0
                 animations:^{
                     imageToMove.transform = CGAffineTransformMakeRotation(M_PI);
                 } 
                 completion:^(BOOL finished){
                     NSLog(@"Done!");
                 }];

但如果我使用2*pi，它根本不会移动(因为它是相同的位置)。如果我尝试只做(180度)，它可以工作，但如果我再次调用这个方法，它会向后旋转。

编辑:

[UIView animateWithDuration:1.0
                      delay:0.0
                    options:0
                 animations:^{
                     [UIView setAnimationRepeatCount:HUGE_VALF];
                     [UIView setAnimationBeginsFromCurrentState:YES];
                     imageToMove.transform = CGAffineTransformMakeRotation(M_PI);
                 } 
                 completion:^(BOOL finished){
                     NSLog(@"Done!");
                 }];

也不管用。它会转到180度，暂停一秒钟，然后在重新开始之前重置回0度。

当前回答

使用UIView执行360度动画有以下几种不同的方法。

使用CABasicAnimation

var rotationAnimation = CABasicAnimation()
rotationAnimation = CABasicAnimation.init(keyPath: "transform.rotation.z")
rotationAnimation.toValue = NSNumber(value: (Double.pi))
rotationAnimation.duration = 1.0
rotationAnimation.isCumulative = true
rotationAnimation.repeatCount = 100.0
view.layer.add(rotationAnimation, forKey: "rotationAnimation")

下面是UIView的一个扩展函数，它处理启动和停止旋转操作:

extension UIView {

    // Start rotation
    func startRotation() {
        let rotation = CABasicAnimation(keyPath: "transform.rotation.z")
        rotation.fromValue = 0
        rotation.toValue = NSNumber(value: Double.pi)
        rotation.duration = 1.0
        rotation.isCumulative = true
        rotation.repeatCount = FLT_MAX
        self.layer.add(rotation, forKey: "rotationAnimation")
    }

    // Stop rotation
    func stopRotation() {
        self.layer.removeAnimation(forKey: "rotationAnimation")
    }
}

现在使用UIView。动画关闭:

UIView.animate(withDuration: 0.5, animations: { 
      view.transform = CGAffineTransform(rotationAngle: (CGFloat(Double.pi)) 
}) { (isAnimationComplete) in
    // Animation completed 
}

2017-07-31 11:40:39

其他回答

这是我的快速解决方案作为一个UIView扩展。它可以被认为是任何UIImageView上UIActivityIndicator行为的模拟。

import UIKit

extension UIView
{

    /**
    Starts rotating the view around Z axis.

    @param duration Duration of one full 360 degrees rotation. One second is default.
    @param repeatCount How many times the spin should be done. If not provided, the view will spin forever.
    @param clockwise Direction of the rotation. Default is clockwise (true).
     */
    func startZRotation(duration duration: CFTimeInterval = 1, repeatCount: Float = Float.infinity, clockwise: Bool = true)
    {
        if self.layer.animationForKey("transform.rotation.z") != nil {
            return
        }
        let animation = CABasicAnimation(keyPath: "transform.rotation.z")
        let direction = clockwise ? 1.0 : -1.0
        animation.toValue = NSNumber(double: M_PI * 2 * direction)
        animation.duration = duration
        animation.cumulative = true
        animation.repeatCount = repeatCount
        self.layer.addAnimation(animation, forKey:"transform.rotation.z")
    }


    /// Stop rotating the view around Z axis.
    func stopZRotation()
    {
        self.layer.removeAnimationForKey("transform.rotation.z")
    }

}

2016-04-15 09:13:59

斯威夫特4.0

func rotateImageView()
{
    UIView.animate(withDuration: 0.3, delay: 0, options: .curveLinear, animations: {() -> Void in
        self.imageView.transform = self.imageView.transform.rotated(by: .pi / 2)
    }, completion: {(_ finished: Bool) -> Void in
        if finished {
            rotateImageView()
        }
    })
}

2017-10-27 13:55:51

@ram的回答很有帮助。以下是Swift版本的答案。

斯威夫特2

private func rotateImageView() {

    UIView.animateWithDuration(1, delay: 0, options: UIViewAnimationOptions.CurveLinear, animations: { () -> Void in
        self.imageView.transform = CGAffineTransformRotate(self.imageView.transform, CGFloat(M_PI_2))
        }) { (finished) -> Void in
            if finished {
                self.rotateImageView()
            }
    }
}

斯威夫特3、4、5所示

private func rotateImageView() {

    UIView.animate(withDuration: 1, delay: 0, options: UIView.AnimationOptions.curveLinear, animations: { () -> Void in
        self.imageView.transform = self.imageView.transform.rotated(by: .pi / 2)
    }) { (finished) -> Void in
        if finished {
            self.rotateImageView()
        }
    }
}

2016-01-05 03:50:01

这对我很管用:

[UIView animateWithDuration:1.0
                animations:^
{
    self.imageView.transform = CGAffineTransformMakeRotation(M_PI);
    self.imageView.transform = CGAffineTransformMakeRotation(0);
}];

2016-02-29 18:49:38