title: UIDocumentInteractionController and lazy loading
body: <p><strong>EDIT :</strong> Is it possible to open remote file ? Or I must download it before ?</p>
  
  <p>How can I show an empty <code>UIDocumentInteractionController</code>, while the file to show is downloading, and once downloaded, refresh the <code>UIDocumentInteractionController</code> to show the file ? Thanks.</p>