protected override void OnCreate(Bundle savedInstanceState)
        {
            base.OnCreate(savedInstanceState);

            // Set our view from the "main" layout resource
            SetContentView(Resource.Layout.Main);

            editTextRegistrationId = FindViewById <EditText> (Resource.Id.editTextRegistrationId);

            // Register for the token refresh, simply to update the UI
            MyRegistrationService.TokenRefreshed += token => {
                RunOnUiThread(() => {
                    editTextRegistrationId.Text = token;
                });
            };

            // Get the last token registered and display immediately
            var p = GetSharedPreferences("gcmsample", FileCreationMode.Private);

            editTextRegistrationId.Text = p.GetString("gcm-token", "N/A");

            // Initiate GCM registration to see if a new token is returned
            MyRegistrationService.Register(this);
        }
 public override void OnTokenRefresh()
 {
     MyRegistrationService.Register(this);
 }