error in Button Jiggle algorithm

objective-c, xcode

Solution

You're setting the animation on `self.btnOption1`, so you would need to remove it from `self.btnOption1`:

- (void)stopJiggling {
    [self.btnOption1.layer removeAllAnimations];
    self.btnOption1.transform = CGAffineTransformIdentity;
}

but in fact if you just set the `transform` property of the button again, outside of an animation block, it will remove the animation:

- (void)stopJiggling {
    self.btnOption1.transform = CGAffineTransformIdentity;
}

(This worked in my test project.)

Update:

I notice that you're starting the animation with a delay, and you're calling `stopJiggling` immediately after you call `animateWithDuration:...`. I don't know why you're using a delay or why you're calling `stopJiggling` immediately.

I created a test case to match your code:

@implementation ViewController {
    __unsafe_unretained IBOutlet UIButton *btnOption1;
}

- (IBAction)startJiggling {
    btnOption1.transform = CGAffineTransformMakeRotation(-.1);
    [UIView animateWithDuration:.1 delay:2 * 0.08 options:UIViewAnimationOptionAllowUserInteraction | UIViewAnimationOptionRepeat | UIViewAnimationOptionAutoreverse animations:^{
        btnOption1.transform = CGAffineTransformMakeRotation(.1);
    } completion:nil];
    [self stopJiggling];
}

- (void)stopJiggling {
    [btnOption1.layer removeAllAnimations];
    btnOption1.transform = CGAffineTransformIdentity;
}

@end

I hooked up my `btnOption1` ivar to a button, and connected the button to the `startJiggling` method. With the code as shown, clicking the button does nothing, because the animation is removed immediately after it is added. If I comment out the `removeAllAnimations` message, clicking the button makes the button start jiggling and it jiggles forever. I tested on the iPhone 4.3 simulator, the iPhone 5.0 simulator, the iPhone 5.1 simulator, and my iPhone 4S running iOS 5.1.

So, I could not reproduce your problem. Sending `removeAllAnimations` removes the animation in my test.

I suspect that you just want the animation to repeat twice and then stop (since you have an argument named `count` and you're passing 2). If that's what you want to do, you can do it like this:

- (IBAction)startJiggling {
    btnOption1.transform = CGAffineTransformMakeRotation(-.1);
    [UIView animateWithDuration:.1 delay:2 * 0.08 options:UIViewAnimationOptionAllowUserInteraction | UIViewAnimationOptionRepeat | UIViewAnimationOptionAutoreverse animations:^{
        [UIView setAnimationRepeatCount:2];
        btnOption1.transform = CGAffineTransformMakeRotation(.1);
    } completion:^(BOOL completed){
        btnOption1.transform = CGAffineTransformIdentity;
    }];
}

You set the repeat count inside the animation block using `+[UIView setAnimationRepeatCount:]`, and you restore the button's transform in the completion block.

Problem

Original source