MainActivity.java

 LocationManager locationManager = (LocationManager) getActivity().getSystemService(LOCATION_SERVICE);
 //Get current location to start with
  Location myLocation = locationManager.getLastKnownLocation(LocationManager.PASSIVE_PROVIDER);

        currentLatitude = myLocation.getLatitude();
        currentLongitude = myLocation.getLongitude();
        
 // Request location update using LocationManager.NETWORK_PROVIDER
 
     locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER,
                MIN_TIME_BW_UPDATES,
                MIN_DISTANCE_CHANGE_FOR_UPDATES, MapFragment.this);