关于动画

最开始的想法是让旋转的弧度从0到2 * M_PI,  让动画不停的repeat，实验了一下，没有任何效果，系统动画的时候看到0与2 ＊M_PI是同一起一始点，所以没有效果。

后来想到一种办法，就是一个变量不断的累加变大，这样影响弧度也随着变化，就达到了圆周运动的效果。

 

直接上代码：

 

-(void) startAnimation
{
    [UIView beginAnimations:nil context:nil];
    [UIView setAnimationDuration:0.01];
    [UIView setAnimationDelegate:self];
    [UIView setAnimationDidStopSelector:@selector(endAnimation)];
    imageView.transform = CGAffineTransformMakeRotation(angle * (M_PI / 180.0f));
    [UIView commitAnimations];
}

-(void)endAnimation
{
    angle += 10;
    [self startAnimation];
}

-(void) startAnimation
{
	[UIView beginAnimations:nil context:nil];
	[UIView setAnimationDuration:0.01];
	[UIView setAnimationDelegate:self];
	[UIView setAnimationDidStopSelector:@selector(endAnimation)];
	imageView.transform = CGAffineTransformMakeRotation(angle * (M_PI / 180.0f));
	[UIView commitAnimations];
}

-(void)endAnimation
{
	angle += 10;
	[self startAnimation];
}

当然你可以用block的方式写也是一样的。

 

 

- (void)startAnimation
{
    CGAffineTransform endAngle = CGAffineTransformMakeRotation(imageviewAngle * (M_PI / 180.0f));

    [UIView animateWithDuration:0.01 delay:0 options:UIViewAnimationOptionCurveLinear animations:^{
        imageView.transform = endAngle;
    } completion:^(BOOL finished) {
        angle += 10; [self startAnimation];
    }];

}

- (void)startAnimation
{
    CGAffineTransform endAngle = CGAffineTransformMakeRotation(imageviewAngle * (M_PI / 180.0f));
    
    [UIView animateWithDuration:0.01 delay:0 options:UIViewAnimationOptionCurveLinear animations:^{
        imageView.transform = endAngle;
    } completion:^(BOOL finished) {
        angle += 10; [self startAnimation];
    }];
    
}

 

 

PS：其中angle是double类型。

 

这下就可以360度旋转了。

 

还有一种方法：

 

CABasicAnimation* rotationAnimation;
rotationAnimation = [CABasicAnimation animationWithKeyPath:@"transform.rotation.z"];
rotationAnimation.toValue = [NSNumber numberWithFloat: M_PI * 2.0 ];
rotationAnimation.duration = duration;
rotationAnimation.cumulative = YES;
rotationAnimation.repeatCount = repeat;

[_loadingView.layer addAnimation:rotationAnimation forKey:@"rotationAnimation"];