title: UI gets black on calling AsyncTask
body: <p>In <code>onCreate()</code> I'm showing a <code>ProgressDialog</code> and then calling <code>AsyncTask</code>  which is non <br/><code>Activity</code>. In this situation the screen goes black up to 30 seconds. How can I <br/>resolve  black ui issue? </p>
  
  <p>this from Activity </p>
  
  <pre><code>showdialog("Your call is being connected with available agent...Please wait!"); 
  response = new GetAvailableLink(ConferenceActivity.this).execute()
                  .get();
  </code></pre>