title: showing/hiding UIToolbar in a UINavigationController without leaving a gap during push/pop transition
body: <p>I have a UINavigationController with two UIViewControllers. One of the ViewController hides the UIToolbar (the default UIToolbar from the UINavigationController) the other shows it. When I push the ViewController with the UIToolbar onto the ViewController without the UIToolbar the following happens:</p>
  
  <p>The UIToolbar slides up from the bottom and fills a black gap in the new ViewController. This is very ugly since you can see the black background, which is different from the rest and the animation should ideally mirror the navigationbar animation (slide from right to left). When I pop the ViewController the opposite happens (hiding the UIToolbar slides down to the bottom and leaves a black gap in the popped ViewController)</p>
  
  <p>I hope this makes sense. I just want the UIToolbar to mirror the navigationbar animation (slide from left to right (pop) and right to left (push) ).</p>
  
  <p>I've done research here on SO but couldn't find a satisfactory answer. Is it possible to make the default UIToolbar behave in the manner I described or is it really necessary to create a custom UIToolbar and add it to the ViewController (which doesn't seem very logical since there is a perfectly good one readily available).</p>
  
  <p>Thanks for you consideration!</p>
  
  <p>Regards,
  Ivo</p>