@Override
  public void onPause() {
    super.onPause();

    // stop geolocation
    if (mGeolocation != null) mGeolocation.stop();
  }
  @Override
  public void onActivityCreated(Bundle savedInstanceState) {
    super.onActivityCreated(savedInstanceState);

    // start geolocation
    if (mLocation == null) {
      mGeolocation = null;
      mGeolocation =
          new Geolocation(
              (LocationManager) getActivity().getSystemService(Context.LOCATION_SERVICE), this);
    }
  }