title: iOS empty popover
body: <p>I am trying to show a picker view in a popover on iPad, but the popover is empty</p>
  
  <pre><code>case timezoneSetting: {
          UIViewController *pickerViewController = (setting.type == timeSetting) ?
                  [[[TimePickerViewController alloc] initWithSetting:setting] autorelease] :
                  [[[TimeZonePickerViewController alloc] initWithSetting:setting] autorelease];
  
          if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad) {
              CGRect frame = [self.tableView rectForRowAtIndexPath:indexPath];
              CGRect cellRect = CGRectMake(frame.origin.x, frame.origin.y - tableView.contentOffset.y, frame.size.width, frame.size.height);
  
              [pickerPopover setContentViewController:[[[UINavigationController alloc] initWithRootViewController:pickerViewController] autorelease]];
              [pickerPopover presentPopoverFromRect:cellRect inView:self.view permittedArrowDirections:(UIPopoverArrowDirectionRight | UIPopoverArrowDirectionUp) animated:YES];
          }
          else {
              [self.navigationController pushViewController:pickerViewController animated:YES];
          }
  
          break;
      }
  </code></pre>