FusedLocationProviderClient gives different location sometimes

Question

 public void getDeviceLocation() {
        fusedLocationClient = LocationServices.getFusedLocationProviderClient(getMvpView().getActivity());
        settingsClient = LocationServices.getSettingsClient(getMvpView().getActivity());
        createLocationCallback();
        createLocationRequest();
        buildLocationSettingsRequest();
        startLocationUpdates();
    }


    private void createLocationRequest() {
        locationRequest = new LocationRequest();
        locationRequest.setInterval(UPDATE_INTERVAL_IN_MILLISECONDS);
        locationRequest.setFastestInterval(FASTEST_UPDATE_INTERVAL_IN_MILLISECONDS);
        locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
    }


    private void createLocationCallback() {
        getMvpView().showProgressDialog();
        locationCallback = new LocationCallback() {
            @Override
            public void onLocationResult(LocationResult locationResult) {
                super.onLocationResult(locationResult);
                Location currentLocation = locationResult.getLastLocation();
                getMvpView().showSelectedAddress(getAddressFromLatLng(currentLocation.getLatitude(), currentLocation.getLongitude()));
                fusedLocationClient.removeLocationUpdates(locationCallback);
                getMvpView().hideProgressDialog();
            }
        };
    }


    private void buildLocationSettingsRequest() {
        LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder();
        builder.addLocationRequest(locationRequest);
        locationSettingsRequest = builder.build();
    }


    private void startLocationUpdates() {
        settingsClient.checkLocationSettings(locationSettingsRequest)
                .addOnSuccessListener(getMvpView().getActivity(), locationSettingsResponse -> {

                    if (ActivityCompat.checkSelfPermission(getMvpView().getActivity(), Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(getMvpView().getActivity(), Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
                        return;
                    }
                    fusedLocationClient.requestLocationUpdates(locationRequest,
                            locationCallback, Looper.myLooper());

                }).addOnFailureListener(getMvpView().getActivity(), e -> {
            getMvpView().hideProgressDialog();
            getMvpView().showErrorToast(R.string.please_enable_location);
        });
    }


    @SuppressLint("MissingPermission")
    private void startLocationUpdates() {
        settingsClient.checkLocationSettings(locationSettingsRequest)
                .addOnSuccessListener(getMvpView().getActivity(), locationSettingsResponse -> {
                    fusedLocationClient.requestLocationUpdates(locationRequest,
                            locationCallback, Looper.myLooper());

                }).addOnFailureListener(getMvpView().getActivity(), e -> {
            getMvpView().hideProgressDialog();
            getMvpView().showErrorToast(R.string.please_enable_location);
        });
    }


    private String getAddressFromLatLng(double latitude, double longitude) {
        Geocoder geocoder = new Geocoder(getMvpView().getActivity(), Locale.getDefault());
        List<Address> addresses = null;
        try {
            addresses = geocoder.getFromLocation(
                    latitude,
                    longitude,
                    1);
        } catch (IOException e) {
            e.printStackTrace();
        }

        Address address = addresses.get(0);
        StringBuilder addressStringBuilder = new StringBuilder();
        for (int i = 0; i <= address.getMaxAddressLineIndex(); i++) {
            addressStringBuilder.append(address.getAddressLine(i));
        }

        return addressStringBuilder.toString();
    }

I have converted the lat, lng to address text but after i query again for location the address changes even i have not moved from my current location, enabled accuracy in phone settings too. The issue is when i always query it should give me the same location address if my lat, lng postion is not changed.

Some fluctuation in the GPS based location is normal. It could be meters or even tens of meters. And the network (cell tower) based location can change even more, as it's not so accurate. So, maybe the geocoding works as expected, but the coordinates actually change enough to affect the result. — Markus Kauppinen, Dec 07 '18 at 09:46

k3b · Accepted Answer · 2018-12-07T11:18:03.700

FusedLocationProviderClient means combining gps and google-translating-received-wlan-cellphone-tower-signals-to-lat-lon.

The google-translating-received-wlan-cellphone-tower-signals-to-lat-lon is an inexact heuristics that among other factors depends to which cellphone-tower your handy is connected to (and where google has lat/lon for each tower) and how stronge the strongest 3 cellphonetowers are.

If your cellphone changes it's cellphone-tower-connection then for googl-s algorithm your phone position has changed.

If your cellphone can receive more than 3 cellphone towers the strongest 3 cellphonetowers will also change depending how much trafic each celltower has.

A gps-receiver costs a lot of energy. When gps-energy-optimisation is enabled then there may be also gps-precision issuses causing the fused location to jump.

I learned this the hard way when doing geocaching for the first time with my brand new cellpone and wondered why my own position jumped in the map

FusedLocationProviderClient gives different location sometimes

1 Answers1