iPhone UIView Animation Disables UIButton Subview

Question

So I've got a problem with buttons and animations. Basically, I'm animating a view using the UIView animations while also trying to listen for taps on the button inside the view. The view is just as large as the button, and the view is actually a subclass of UIImageView with an image below the button. The view is a subview of a container view placed in Interface Builder with user interaction enabled and clipping enabled. All the animation and button handling is done in this UIImageView subclass, while the startFloating message is sent from a separate class as needed.

If I do no animation, the buttonTapped: message gets sent correctly, but during the animation it does not get sent. I've also tried implementing the touchesEnded method, and the same behavior occurs.

UIImageView subclass init (I have the button filled with a color so I can see the frame gets set properly, which it does):

- (id)initWithImage:(UIImage *)image {
    self = [super initWithImage:image];
    if (self != nil) {
        // ...stuffs

        UIButton *tapBtn = [UIButton buttonWithType:UIButtonTypeCustom];
        tapBtn.frame = CGRectMake(0, 0, self.frame.size.width, self.frame.size.height);
        [tapBtn addTarget:self action:@selector(buttonTapped:) forControlEvents:UIControlEventTouchUpInside];
        tapBtn.backgroundColor = [UIColor cyanColor];
        [self addSubview:tapBtn];

        self.userInteractionEnabled = YES;
    }
    return self;
}

Animation method that starts the animation (if I don't call this the button works correctly):

- (void)startFloating {
    [UIView beginAnimations:@"floating" context:nil];
    [UIView setAnimationDelegate:self];
    [UIView setAnimationCurve:UIViewAnimationCurveLinear];
    [UIView setAnimationDuration:10.0f];
    self.frame = CGRectMake(self.frame.origin.x, -self.frame.size.height, self.frame.size.width, self.frame.size.height);
    [UIView commitAnimations];
}

So, to be clear:

• Using the UIView animation effectively disables the button.
• Disabling the animation causes the button to work.
• The button is correctly sized and positioned on screen, and moves along with the view correctly.

Answer 1

The animation is just eye candy. The animation lags behind the actual movement of the view. The button is already at the destination point when the animation starts. You just see a movie of the view/button moving.

If you want a button to be clickable during the animation, you'll have to make the animation yourself.

Answer 2

Hey Ben - any chance you can post the code you used to get this working? I'm having the same issue at the minute. Was hoping I could avoid using an NSTimer since I have multiple buttons that need animating at once... Guess not!