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

创建动画

- (CABasicAnimation *)spinAnimationWithDuration:(CGFloat)duration clockwise:(BOOL)clockwise repeat:(BOOL)repeats
{
    CABasicAnimation *anim = [CABasicAnimation animationWithKeyPath:@"transform.rotation.z"];
    anim.toValue = clockwise ? @(M_PI * 2.0) : @(M_PI * -2.0);
    anim.duration = duration;
    anim.cumulative = YES;
    anim.repeatCount = repeats ? CGFLOAT_MAX : 0;
    return anim;
}

将它添加到这样的视图中

CABasicAnimation *animation = [self spinAnimationWithDuration:1.0 clockwise:YES repeat:YES];
[self.spinningView.layer addAnimation:animation forKey:@"rotationAnimation"];

这个答案有什么不同?如果你的大部分函数都返回对象,而不是在这里和那里操作一些对象,你会有更干净的代码。

其他回答

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()
        }
    })
}

这对我很管用:

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

我的贡献与一个快速扩展从检查解决方案:

斯威夫特4.0

extension UIView{
    func rotate() {
        let rotation : CABasicAnimation = CABasicAnimation(keyPath: "transform.rotation.z")
        rotation.toValue = NSNumber(value: Double.pi * 2)
        rotation.duration = 1
        rotation.isCumulative = true
        rotation.repeatCount = Float.greatestFiniteMagnitude
        self.layer.add(rotation, forKey: "rotationAnimation")
    }
}

弃用:

extension UIView{
    func rotate() {
        let rotation : CABasicAnimation = CABasicAnimation(keyPath: "transform.rotation.z")
        rotation.toValue = NSNumber(double: M_PI * 2)
        rotation.duration = 1
        rotation.cumulative = true
        rotation.repeatCount = FLT_MAX
        self.layer.addAnimation(rotation, forKey: "rotationAnimation")
    }
}

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)

    }

}

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 
}