Problems with UIView Animation of frame property

Question

Hallo!

That's really strange.. i'm changing the frame between two states. In case one, it's animated correctly, in case two (back to original size) only x/y is animated, but width/height instantly changes. Any Idea?

Greetz

// strange behavior
 [UIView beginAnimations: @"photobtn" context: nil];
 [UIView setAnimationDuration: 0.15];

 if (CGRectGetWidth(mPhotoButton.frame) == CGRectGetWidth(mOriginalPhotoFrame)) {

  int margin = 10;

  CGRect frame = mMapView.frame;
  frame.size.width -= margin*2;
  frame.size.height -= margin*2;
  frame.origin.x += margin;
  frame.origin.y += margin;

  mPhotoButton.frame = frame;
 } else {

  mPhotoButton.frame = mOriginalPhotoFrame;
 }

 [UIView commitAnimations];