Question

I am currently working on the implementation of a slideshow control in an iPad application.

I would like to manage different kinds of transitions between the images, particularly the UIViewAnimationOptionTransitionCurlUp.

My ViewController’s xib is composed of two superposed UIImageViews, with a UIToolbar over the two UIImageViews in order to give the user a play/pause control.

Here is how it looks like :

I today face the problem that when the CurlUp transition occurs between my two UIImageViews, I see the UIToolbar (which is normally over the two other views) animate as well :

Here is how my transition code looks like :

if ([slideshow.images count] <= 1)
{
    return;
}
currentImageIndex = ((currentImageIndex + 1) >= [slideshow.images count]) ? 0 : currentImageIndex + 1;

//imageStackView contains the two UIImageViews bound as IBOutlets from my xib
UIImageView *loadingImageView = [imageViewStack objectAtIndex:1];
loadingImageView.image = [slideshow.images objectAtIndex:currentImageIndex];
UIImageView *currentImageView = [imageViewStack objectAtIndex:0];

[UIView transitionFromView:currentImageView
                    toView:loadingImageView
                  duration:slideshow.duration
                   options:UIViewAnimationOptionTransitionCurlUp
                completion:^(BOOL finished) {
                      UIImageView *swap = [imageViewStack objectAtIndex:0];
                      [self.view bringSubviewToFront:toolbar];
                      [imageViewStack removeObjectAtIndex:0];
                      [imageViewStack addObject:swap];
                      [self scheduleNextAnimation];
        }];

Please let me know if you have any idea about this !

Thanks in advance !

Answer 1

I solved this problem by appending the two UIImageViews in my nib in a parent UIView.
As a result, I have a view hierarchy as following :

• UIView
  • UIView (parent view for UIImageViews)
    • UIImageView
    • UIImageView
  • UIToolbar