title: Animating UIView frame size change with autoresizing subviews
body: <p>I have a UIView which contains two subviews. I would like to change the superview's frame size with an animation and have the subviews' sizes change in accordance with their autoresize masks. </p>
  
  <pre><code>[UIView beginAnimations:@"Resize" context:nil];
  [UIView setAnimationDuration:1.0];
  CGRect frame = self.myView.frame;
  frame.size.height += 30.0;
  self.myView.frame = frame;
  [UIView commitAnimations];
  </code></pre>
  
  <p>The view <code>self.myView</code> is resized over 1 second as expected, but the subviews are resizing immediately. Does anyone know why this is happening and how I might make the subviews animate their resizing as well?</p>
  
  <p>From my googling around, I think it might have something to with the <code>contentMode</code> property. Unfortunately, I'm not  really clear as to what that property does. Any help would be much appreciated.</p>