title: UIPopoverPresentationController Fade In
body: <p>In my iOS8+ project, I am presenting a UIViewController using UIPopoverPresentationController:</p>
  
  <pre><code>vc.modalPresentationStyle = UIModalPresentationPopover;
  vc.popoverPresentationController.delegate = self;
  vc.popoverPresentationController.sourceView = self.someView.superview;
  vc.popoverPresentationController.sourceRect = self.someView.frame;
  vc.popoverPresentationController.backgroundColor = [UIColor clearColor];
  vc.popoverPresentationController.permittedArrowDirections = UIPopoverArrowDirectionUp | UIPopoverArrowDirectionDown;
  vc.preferredContentSize = CGSizeMake(200, 500);
  </code></pre>
  
  <p>(Also implementing the delegate method to force as popover)</p>
  
  <pre><code>-(UIModalPresentationStyle)adaptivePresentationStyleForPresentationController:(UIPresentationController *)controller
  {
      return UIModalPresentationNone;
  }
  </code></pre>
  
  <p>Currently, it appears instantly over the presenting UIViewController (and disappears with fade out). Can anyone direct me towards customizing this presentation so I can make it fade in?</p>