title: Update TextView from GCMIntentService in Methods onRegistered and onUnregistered
body: <p>I want to set the text of a TextView in my MainActivity with the onRegistered and onUnregistered methods in the GCMIntentService class I've implemented. I can't set it directly because it's in a different class. What would be the best way to handle this?</p>
  
  <p>A little background. I"m using the TextView to update the status on whether the device is registered or not and to display messages to the user. The reason I want to set it in the GCMIntentService is because once those methods are deplyed the device has completed the tasks. Right now when the user hits the register button it switches the status to registered, but the device isn't fully registered yet. I don't want to cause confusion or errors because they think the device is registered.</p>