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

我发现了一个非常适合我的方法(我稍微修改了一下):iphone UIImageView旋转

#import <QuartzCore/QuartzCore.h>

- (void) runSpinAnimationOnView:(UIView*)view duration:(CGFloat)duration rotations:(CGFloat)rotations repeat:(float)repeat {
    CABasicAnimation* rotationAnimation;
    rotationAnimation = [CABasicAnimation animationWithKeyPath:@"transform.rotation.z"];
    rotationAnimation.toValue = [NSNumber numberWithFloat: M_PI * 2.0 /* full rotation*/ * rotations * duration ];
    rotationAnimation.duration = duration;
    rotationAnimation.cumulative = YES;
    rotationAnimation.repeatCount = repeat ? HUGE_VALF : 0;

    [view.layer addAnimation:rotationAnimation forKey:@"rotationAnimation"];
}

其他回答

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];

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)

    }

}

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

我已经开发了一个闪亮的动画框架,可以节省你的时间! 使用它可以很容易地创建这个动画:

private var endlessRotater: EndlessAnimator!
override func viewDidAppear(animated: Bool) 
{
    super.viewDidAppear(animated)
    let rotationAnimation = AdditiveRotateAnimator(M_PI).to(targetView).duration(2.0).baseAnimation(.CurveLinear)
    endlessRotater = EndlessAnimator(rotationAnimation)
    endlessRotater.animate()
}

要停止这个动画,只需将nil设置为endlessRotater。

如果你感兴趣,请看看:https://github.com/hip4yes/Animatics

import UIKit

class RotatingImageView: UIImageView, CAAnimationDelegate {
    
    private let rotationAnimationKey = "rotationAnimationKey"

    private var shouldStopRotating = false
    
    func startRotating(witFullRotationDuration duration: Double = 0.5, halfRotation: Bool = true) {
        
        shouldStopRotating = false
        if layer.animation(forKey: rotationAnimationKey) == nil {
        
            let rotationAnimation = CABasicAnimation(keyPath: "transform.rotation")
            rotationAnimation.fromValue = 0.0
            rotationAnimation.toValue = halfRotation ? Float.pi : Float.pi * 2
            rotationAnimation.duration = duration
            rotationAnimation.repeatCount = 1
            rotationAnimation.delegate = self
            layer.add(rotationAnimation, forKey: rotationAnimationKey)
        
        }
        
    }

    func stopRotating(immediately: Bool = false) {
        if immediately {
            if layer.animation(forKey: rotationAnimationKey) != nil {
                layer.removeAnimation(forKey: rotationAnimationKey)
            }
        } else {
            shouldStopRotating = true
        }
    }
    
    func animationDidStop(_ anim: CAAnimation, finished flag: Bool) {
    
        if !shouldStopRotating {
            startRotating(witFullRotationDuration: anim.duration)
        } else {
            if layer.animation(forKey: rotationAnimationKey) != nil {
                layer.removeAnimation(forKey: rotationAnimationKey)
            }
        }
        
    }
    
}