title: How to add back or cancel button to dismiss UIDocumentBrowser
body: <p>I need to present UIDocumentBrowser for uploading a document. But I am not able to place a back or cancel button in the navigation bar. The image below is a screenshot of the file browser in WhatsApp. 
  Can anybody help me?</p>
  
  <p><a href="https://i.stack.imgur.com/oaymd.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/oaymd.png" alt="enter image description here"></a></p>