title: Status bar Hidden Issue, when present QLPreview controller
body: <p>Following is my code:</p>
  
  <pre><code>QLPreviewController *previewController=[[QLPreviewController alloc]init];
  
  previewController.delegate = self;
  previewController.dataSource = self;
  [self presentViewController:previewController animated:YES completion:NULL]; 
  </code></pre>
  
  <p>I have set <strong>ViewController</strong> based status bar property to NO.</p>
  
  <p>When I present <strong>QLPreviewController</strong>, the status bar is hidden.
  Kindly tell me the solution of this problem.</p>