I'm trying to run an activity through a notification and event onCreate I would like to "redirect". To this add a thought on information in the Intent class. An important feature is that the class that generates the notification is performed through a service. I retrieve the context from getApplicationContext method provided by the class android.app.Application. Whenever I call method getExtras() is returning null. What am I doing wrong?
public class OXAppUpdateHandler {
    private void addNotification(Context context, int iconID,
           CharSequence tickerText, CharSequence title, CharSequence content) {
        CharSequence notificationTicket = tickerText;
        CharSequence notificationTitle = title;
        CharSequence notificationContent = content;
        long when = System.currentTimeMillis();
        Intent intent = new Intent(context, MainActivity_.class);
        intent.setFlags(
            Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_SINGLE_TOP);
        intent.putExtra(OPEN_UPDATE_ACTIVITY_KEY, 1);
        PendingIntent pendingIntent = 
            PendingIntent.getActivity(context, 0, intent, 0);
        NotificationManager notificationManager = 
            (NotificationManager) context.getSystemService(
                Context.NOTIFICATION_SERVICE);
        Notification notification = 
            new Notification(iconID, notificationTicket, when);
        notification.setLatestEventInfo(context, notificationTitle, 
                                        notificationContent, pendingIntent);
        notificationManager.notify(NOTIFICATION_ID, notification);
    }
    public static boolean isUpdateStart(Intent intent) {
        Bundle bundle = intent.getExtras();
        boolean result = bundle != null && 
                         bundle.containsKey(OPEN_UPDATE_ACTIVITY_KEY);
        if (result) {
            bundle.remove(OPEN_UPDATE_ACTIVITY_KEY);
        }
        return result;
        }
    }
    @EActivity(R.layout.activity_main)
    public class MainActivity extends Activity {
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            if (OXAppUpdateHandler.isUpdateStart(getIntent())) {
                startActivity(new Intent(this, UpdateActivity_.class));
            }
        }
    }