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

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()
        }
    })
}

其他回答

使用四分之一转弯,并逐步增加转弯。

void (^block)() = ^{
    imageToMove.transform = CGAffineTransformRotate(imageToMove.transform, M_PI / 2);
}

void (^completion)(BOOL) = ^(BOOL finished){
    [UIView animateWithDuration:1.0
                          delay:0.0
                        options:0
                     animations:block
                     completion:completion];
}

completion(YES);

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 
}

这就是我如何向正确的方向旋转360度。

[UIView animateWithDuration:1.0f delay:0.0f options:UIViewAnimationOptionRepeat|UIViewAnimationOptionCurveLinear
                     animations:^{
                         [imageIndView setTransform:CGAffineTransformRotate([imageIndView transform], M_PI-0.00001f)];
                     } completion:nil];

@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()
        }
    }
}

我在这个库中找到了很好的代码,

下面是它的代码,我做了一些小的改变,根据我的速度需要:)

UIImageView + Rotate.h

#import <Foundation/Foundation.h>

@interface UIImageView (Rotate)
- (void)rotate360WithDuration:(CGFloat)duration repeatCount:(float)repeatCount;
- (void)pauseAnimations;
- (void)resumeAnimations;
- (void)stopAllAnimations;
@end

UIImageView + Rotate.m

#import <QuartzCore/QuartzCore.h>
#import "UIImageView+Rotate.h"

@implementation UIImageView (Rotate)

- (void)rotate360WithDuration:(CGFloat)duration repeatCount:(float)repeatCount
{

    CABasicAnimation *fullRotation;
    fullRotation = [CABasicAnimation animationWithKeyPath:@"transform.rotation"];
    fullRotation.fromValue = [NSNumber numberWithFloat:0];
    //fullRotation.toValue = [NSNumber numberWithFloat:(2*M_PI)];
    fullRotation.toValue = [NSNumber numberWithFloat:-(2*M_PI)]; // added this minus sign as i want to rotate it to anticlockwise
    fullRotation.duration = duration;
    fullRotation.speed = 2.0f;              // Changed rotation speed
    if (repeatCount == 0)
        fullRotation.repeatCount = MAXFLOAT;
    else
        fullRotation.repeatCount = repeatCount;

    [self.layer addAnimation:fullRotation forKey:@"360"];
}

//Not using this methods :)

- (void)stopAllAnimations
{

    [self.layer removeAllAnimations];
};

- (void)pauseAnimations
{

    [self pauseLayer:self.layer];
}

- (void)resumeAnimations
{

    [self resumeLayer:self.layer];
}

- (void)pauseLayer:(CALayer *)layer
{

    CFTimeInterval pausedTime = [layer convertTime:CACurrentMediaTime() fromLayer:nil];
    layer.speed = 0.0;
    layer.timeOffset = pausedTime;
}

- (void)resumeLayer:(CALayer *)layer
{

    CFTimeInterval pausedTime = [layer timeOffset];
    layer.speed = 1.0;
    layer.timeOffset = 0.0;
    layer.beginTime = 0.0;
    CFTimeInterval timeSincePause = [layer convertTime:CACurrentMediaTime() fromLayer:nil] - pausedTime;
    layer.beginTime = timeSincePause;
}

@end