title: Push ViewController with modal animation (horizontal flip)
body: <p>I need to push a view controller to another view controller. </p>
  
  <pre><code>menuVC -&gt; VC1 -&gt;VC2
  </code></pre>
  
  <p>going from menuVC to VC1 requires no animation, but going from VC1 to VC2 and from VC2 to VC1 requires the flip animaton to occur. </p>
  
  <p>However, when going from VC2 to menuVC, no animation is needed.</p>
  
  <p>I am using the following code:</p>
  
  <p>(from <a href="https://stackoverflow.com/questions/7266144/how-to-push-a-viewcontroller-with-flip-animation">how to push a viewController with flip animation</a>)</p>
  
  <pre><code>[UIView beginAnimations:nil context:nil];
  [UIView setAnimationDuration:1];
  [UIView setAnimationCurve:UIViewAnimationCurveEaseIn];
  [UIView setAnimationTransition:UIViewAnimationTransitionFlipFromLeft forView:self.view cache:YES];
  FlashCardVC *flashCardVC = [[FlashCardVC alloc] init];
  [self.navigationController pushViewController:flashCardVC animated:NO];
  [UIView commitAnimations];
  </code></pre>
  
  <p>The screen goes completely blank when I try and do the above. </p>
  
  <p>What is wrong?</p>