title: How do I share files using share sheet in iOS?
body: <p>I want to share some files I have locally in my app using Share Sheet functionality on iPhone. I display the file in a <code>UIWebView</code> and when the user clicks the share sheet, I want to show options (email, WhatsApp, etc. ) to share the file displayed on the <code>UIWebView</code>. I know that we can use</p>
  <pre><code>func displayShareSheet(shareContent:String) {                                                                           
      let activityViewController = UIActivityViewController(activityItems: [shareContent as NSString], applicationActivities: nil)
      presentViewController(activityViewController, animated: true, completion: {})    
  }
  </code></pre>
  <p>to share a string for example. How do I change this code to share documents?</p>