title: Facebook SDK for Unity on Android - Trouble about callback from FB.Login
body: <p>I'm having some problem about login in facebook-unity-sdk on android device. When I login and get callback, them return this </p>
  
  <p>FBResult.Text</p>
  
  <pre><code>{"is_logged_in":false,"user_id":"","access_token":""}
  </code></pre>
  
  <p>FBResult.Error</p>
  
  <pre><code>null
  </code></pre>
  
  <p>and FB.IsLoggedIn is null everytime after login completed</p>
  
  <p>I'm using last version of Facebook SDK (4.2.1) and Unity 4.2</p>
  
  <p>On Debug Log</p>
  
  <pre><code>Send to Unity OnLoginCompleted({"cancelled":true})
  </code></pre>