title: Share image via whatsapp ios 8
body: <p>I am capturing an image in my app and what to share it using WHATSAPP by pressing share button like in RETRICA. But i didn't find any way to do it properly. i used UIDocumentInteraction but it didn't work. How can i share it using share extension of WHATSAPP in IOS8. </p>
  
  <p>I got this exception while using UIDocumentInteractionController.</p>
  
  <p>'UIDocumentInteractionController: invalid scheme (null).  Only the file scheme is supported.'</p>
  
  <p>this is my code</p>
  
  <pre><code>let image = UIImage(named: "nature")
          let path = NSHomeDirectory().stringByAppendingPathComponent("Documents/whatsAppTmp.wai")
          UIImageJPEGRepresentation(image!, 100.0)?.writeToFile(path, atomically: true)
  
          let documentInteractionController = UIDocumentInteractionController(URL: NSURL(string: path)!)
          documentInteractionController.UTI = "net.whatsapp.image"
  </code></pre>