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 
}

其他回答

在Swift中,你可以使用以下代码进行无限旋转:

斯威夫特4

extension UIView {
    private static let kRotationAnimationKey = "rotationanimationkey"

    func rotate(duration: Double = 1) {
        if layer.animation(forKey: UIView.kRotationAnimationKey) == nil {
            let rotationAnimation = CABasicAnimation(keyPath: "transform.rotation")

            rotationAnimation.fromValue = 0.0
            rotationAnimation.toValue = Float.pi * 2.0
            rotationAnimation.duration = duration
            rotationAnimation.repeatCount = Float.infinity

            layer.add(rotationAnimation, forKey: UIView.kRotationAnimationKey)
        }
    }

    func stopRotating() {
        if layer.animation(forKey: UIView.kRotationAnimationKey) != nil {
            layer.removeAnimation(forKey: UIView.kRotationAnimationKey)
        }
    }
}

斯威夫特3

let kRotationAnimationKey = "com.myapplication.rotationanimationkey" // Any key

func rotateView(view: UIView, duration: Double = 1) {
    if view.layer.animationForKey(kRotationAnimationKey) == nil {
        let rotationAnimation = CABasicAnimation(keyPath: "transform.rotation")

        rotationAnimation.fromValue = 0.0
        rotationAnimation.toValue = Float(M_PI * 2.0)
        rotationAnimation.duration = duration
        rotationAnimation.repeatCount = Float.infinity

        view.layer.addAnimation(rotationAnimation, forKey: kRotationAnimationKey)
    }
}

停下来就像:

func stopRotatingView(view: UIView) {
    if view.layer.animationForKey(kRotationAnimationKey) != nil {
        view.layer.removeAnimationForKey(kRotationAnimationKey)
    }
}

迅速:

func runSpinAnimationOnView(view:UIView , duration:Float, rotations:Double, repeatt:Float ) ->()
    {
        let rotationAnimation=CABasicAnimation();

        rotationAnimation.keyPath="transform.rotation.z"

        let toValue = M_PI * 2.0 * rotations ;


        // passing it a float
        let someInterval = CFTimeInterval(duration)

        rotationAnimation.toValue=toValue;
        rotationAnimation.duration=someInterval;
        rotationAnimation.cumulative=true;
        rotationAnimation.repeatCount=repeatt;
        view.layer.addAnimation(rotationAnimation, forKey: "rotationAnimation")


    }

这对我很管用:

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

Swift 5使用关键帧动画的UIView扩展

这个方法允许我们直接使用UIView.AnimationOptions.repeat

public extension UIView {

    func animateRotation(duration: TimeInterval, repeat: Bool, completion: ((Bool) -> ())?) {

        var options = UIView.KeyframeAnimationOptions(rawValue: UIView.AnimationOptions.curveLinear.rawValue)

        if `repeat` {
            options.insert(.repeat)
        }

        UIView.animateKeyframes(withDuration: duration, delay: 0, options: options, animations: {

            UIView.addKeyframe(withRelativeStartTime: 0, relativeDuration: 0.25, animations: {
                self.transform = CGAffineTransform(rotationAngle: CGFloat.pi/2)
            })

            UIView.addKeyframe(withRelativeStartTime: 0.25, relativeDuration: 0.25, animations: {
                self.transform = CGAffineTransform(rotationAngle: CGFloat.pi)
            })

            UIView.addKeyframe(withRelativeStartTime: 0.5, relativeDuration: 0.25, animations: {
                self.transform = CGAffineTransform(rotationAngle: 3*CGFloat.pi/2)
            })

            UIView.addKeyframe(withRelativeStartTime: 0.75, relativeDuration: 0.25, animations: {
                self.transform = CGAffineTransform(rotationAngle: 2*CGFloat.pi)
            })

        }, completion: completion)

    }

}

@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()
        }
    }
}