title: UIDocumentInteractionController not launch
body: <p>I want to download media file to my iOS app and open it with UIDocumentInteractionController. I succesfully download it to sandbox, it is in document folder, and full path is something like:</p>
  
  <pre><code>//Users/Me/Library/Developer/CoreSimulator/Devices/A8350F24-987E-4518-AA24-A984343623A3/data/Containers/Data/Application/4382B031-EDA5-47AB-91CD-A3C4106C2EFF/Documents/downloadedFile
  </code></pre>
  
  <p>Then i try to use UIDocumentInteractionController but nothing happen. Please take a look:</p>
  
  <p>In top of class:</p>
  
  <p>var docController:UIDocumentInteractionController!</p>
  
  <p>Then:</p>
  
  <pre><code>let fm = FileManager.default
  let docsurl = try! fm.url(for:.documentDirectory, in: .userDomainMask, appropriateFor: nil, create: false)
  let myurl = docsurl.appendingPathComponent("downloadedFile")
      self.docController = UIDocumentInteractionController(url: myurl)
  </code></pre>
  
  <p>My path is correct, i can check it by finder. I tried it on real device but still not working.</p>