Custom transition between two UIViews

Question

I have two views \"A\" and \"B\". A floats in the middle of the window (it\'s not full screen). B, the view which will replace A, is full screen. I\'d like to write a custom

Answer 1

I've done this before. Here's the gist of how I did it:

1. View A is on screen
2. Create View B, give it a frame that makes it fullscreen, but don't add it to the screen yet
3. View B has a UIImageView as it's topmost view

4. Capture a UIImage of View A, and set it as the image of View B's image view

   UIGraphicsBeginImageContext(view.bounds.size); 
   [viewA.layer renderInContext:UIGraphicsGetCurrentContext()]; 
   UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
   viewB.imageView.image = image;
   

5. Set View B's transform (scale and translation) so that it is shrunk to the size of View A and is positioned where View A is on the screen

6. Add View B to the screen
7. At this point, the user hasn't noticed anything change, because View B looks exactly like View A
8. Now start an animation block, in which you
   • Set [UIView setAnimationTransition: UIViewAnimationTransitionFlipFromLeft forView:ViewB
   • set View B's transform to CGAffineTransformIdentity
   • remove View B's imageview from View B

The result is an animation that looks like View A is flipping over and zooming to fill the screen with View B as the opposite side.