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。
我认为你最好添加一个UIVIew Category:
#import <QuartzCore/QuartzCore.h>
#import "UIView+Rotate.h"
实现UIView(旋转)
(void)remrotate360WithDuration:(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"];
}
不使用此方法:)
(void)remstopAllAnimations
{
[self.layer removeAllAnimations];
};
(void)rempauseAnimations
{
[self rempauseLayer:self.layer];
}
(void)remresumeAnimations
{
[self remresumeLayer:self.layer];
}
(void)rempauseLayer:(CALayer *)layer
{
CFTimeInterval pausedTime = [layer convertTime:CACurrentMediaTime() fromLayer:nil];
layer.speed = 0.0;
layer.timeOffset = pausedTime;
}
(void)remresumeLayer:(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;
}
@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()
}
}
}
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")
}
}
