title: Status Bar Disappears on Modal Presentation
body: <p>In my iOS app, I am modally presenting a View Controller (AVPlayerViewController, in this case) using a transition.</p>
  
  <p>At the start of the transition, the Status Bar disappears instantly and yanks up the contents of the app in an ugly jerk, before the animation (of whatever kind--crossfade, cover vertical) hides the underlying stack of view controllers.  The new modally presented VC has a status bar on it.</p>
  
  <p>I'd like to not have the status bar vanish at the <em>start</em> of the modal presentation animation.</p>
  
  <p>I set up a blank project and mocked the same basic structure of my app, and when a view controller is presented, the status bar remains stationary during the transition.</p>
  
  <p>What would cause the status bar to vanish at the start of a modal presentation animation?</p>
  
  <p>(Tested on iOS 11 on iPhone X and iOS 10/9 on simulators.)</p>
  
  <p>EDIT:</p>
  
  <p>To perform the presentation, the root view controller of the app is listening for a notification and calling, roughly:</p>
  
  <pre><code>let vc = AVPlayerViewController()
  // configure the player
  self.present(vc, animated: true) {
      vc.player?.play()
  }
  </code></pre>
  
  <p>This is what produces the odd vanishment.</p>
  
  <p>Interestingly, when I go into the Storyboard and set up a Modal Segue (to a blank view controller) from that same root view controller, triggered off a randomly-added-button, the resultant transition is smooth.</p>
  
  <p>Another data point is that when I <em>turn off</em> animation in <code>present(:animated:completion:)</code> the status bar stays put until the modal is covering it.</p>