Location Helper Activity to get continuously updates of location in your child activity. Just extend this activity in your every child activity where you want to get updates.

LocationHelperActivity.java

public abstract class LocationHelperActivity extends AppCompatActivity {

	private static final String TAG = "LocationHelperActivity";

	private static final int PERMISSION_REQUEST_CODE = 200;
	public static final long INTERVAL = 1000 * 3 * 60; // 3 = 3 minutes
	public static final long FASTEST_INTERVAL = 1000 * 60; // 60 = 60 seconds = 1 minutes

	public String mCurrentLatitude = "";
	public String mCurrentLongitude = "";

	//	GoogleApiClient mGoogleApiClient;
	Location mCurrentLocation;
	LocationRequest mLocationRequest;
	private LocationCallback mLocationCallback;
	protected FusedLocationProviderClient mFusedLocationClient;

	@Override
	protected void onResume() {
		super.onResume();
		if (!CommonUses.checkForLocationEnabled(this)) {
			final android.app.AlertDialog.Builder dialog = new android.app.AlertDialog.Builder(LocationHelperActivity.this);
			dialog.setMessage(getString(R.string.alert_gps_title));
			dialog.setCancelable(false);
			dialog.setPositiveButton(getString(R.string.button_open_settings), new DialogInterface.OnClickListener() {
				@Override
				public void onClick(DialogInterface dialogInterface, int paramInt) {
					Intent myIntent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
					startActivity(myIntent);
				}
			});
			dialog.setNegativeButton(getString(R.string.cancel), new DialogInterface.OnClickListener() {
				@Override
				public void onClick(DialogInterface dialogInterface, int paramInt) {
					finish();
				}
			});
			dialog.show();
		}

		startLocationUpdates();
	}

	@Override
	protected void onCreate(@Nullable Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		if (!checkLocationPermission()) {
			ActivityCompat.requestPermissions(this,
					new String[]{ACCESS_COARSE_LOCATION, ACCESS_FINE_LOCATION}, PERMISSION_REQUEST_CODE);
		}

		initGoogleClient();
	}

	/**
	 * All about permission
	 */
	private boolean checkLocationPermission() {
		int result3 = ContextCompat.checkSelfPermission(this, ACCESS_COARSE_LOCATION);
		int result4 = ContextCompat.checkSelfPermission(this, ACCESS_FINE_LOCATION);
		return result3 == PackageManager.PERMISSION_GRANTED &&
				result4 == PackageManager.PERMISSION_GRANTED;
	}

	@Override
	public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
		if (requestCode == PERMISSION_REQUEST_CODE) {
			if (grantResults.length > 0) {
				boolean coarseLocation = grantResults[0] == PackageManager.PERMISSION_GRANTED;
				boolean fineLocation = grantResults[1] == PackageManager.PERMISSION_GRANTED;
				if (coarseLocation && fineLocation)
					Toast.makeText(this, "Permission Granted", Toast.LENGTH_SHORT).show();
				else {
					Toast.makeText(this, "Permission Denied", Toast.LENGTH_SHORT).show();
				}
			}
		}
	}

	@Override
	protected void onPause() {
		super.onPause();
		try {
			stopLocationUpdates();
		} catch (Exception e) {
			Crashlytics.logException(e);
		}
	}

	private void initGoogleClient() {
		mLocationRequest = new LocationRequest();
		mLocationRequest.setInterval(INTERVAL);
		mLocationRequest.setFastestInterval(FASTEST_INTERVAL);
		mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
		mLocationRequest.setSmallestDisplacement(50);
        /*
           BUILDING GOOGLE API CLIENT
        */
		mFusedLocationClient = LocationServices.getFusedLocationProviderClient(this);
		mLocationCallback = new LocationCallback() {
			@Override
			public void onLocationResult(LocationResult locationResult) {
				super.onLocationResult(locationResult);
				mCurrentLocation = locationResult.getLastLocation();
				if (mCurrentLocation != null) {
					double latitude = mCurrentLocation.getLatitude();
					double longitude = mCurrentLocation.getLongitude();
					//Latlong = getFormattedLocationInDegree(location.getLatitude(), location.getLongitude());
					mCurrentLatitude = String.valueOf(latitude);
					mCurrentLongitude = String.valueOf(longitude);

					onNewLocation(latitude, longitude);

					Log.i(TAG, "Last Location Request :" + mCurrentLatitude + "," + mCurrentLongitude);
				}
			}
		};
	}

	private void startLocationUpdates() {
		if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED &&
				ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) == PackageManager.PERMISSION_GRANTED) {
			try {
				Log.d(TAG, "update started.......................");
				mFusedLocationClient
						.getLastLocation()
						.addOnCompleteListener(new OnCompleteListener<Location>() {
							@Override
							public void onComplete(@NonNull Task<Location> task) {
								if (task.isSuccessful() && task.getResult() != null) {
									mCurrentLocation = task.getResult();
									if (mCurrentLocation != null) {
										double latitude = mCurrentLocation.getLatitude();
										double longitude = mCurrentLocation.getLongitude();

										mCurrentLatitude = String.valueOf(latitude);
										mCurrentLongitude = String.valueOf(longitude);
										Log.i(TAG, "Updated Location Request :" + mCurrentLocation.getLatitude() + "," + mCurrentLocation.getLongitude());

										onNewLocation(latitude, longitude);
									}
								} else {
									Log.w(TAG, "Failed to get location.");
								}
							}
						});

				mFusedLocationClient.requestLocationUpdates(mLocationRequest, mLocationCallback, Looper.myLooper());
			} catch (SecurityException unlikely) {
				Log.e(TAG, "Lost location permission. Could not request updates. " + unlikely);
			}
		}
	}

	protected void updateLocation() {
		startLocationUpdates();
	}

	private void stopLocationUpdates() {
		try {
			mFusedLocationClient.removeLocationUpdates(mLocationCallback);
			Log.d(TAG, "Location update stopped .......................");
		} catch (Exception e) {
			Crashlytics.logException(e);
		}
	}

	protected void onNewLocation(double latitude, double longitude){ }
}