FusedLocationProviderClient doesn't have bearing data

Question

I'm using FusedLocationProviderClient class in android to get user's last location. Everything is fine and I can get latitude and longitude but task.getResult().getBearing() returns 0.0 and task.getResult().hasBearing() returns false. How can I get user's bearing information?

I'm getting ACCESS_FINE_LOCATION and ACCESS_COARSE_LOCATION permissions both in AndroidManifest file and at runtime.

This is the piece of code related to user location I'm using:

@SuppressLint("MissingPermission")
private void getLastLocation() {
    fusedLocationClient
            .getLastLocation()
            .addOnCompleteListener(this, new OnCompleteListener<Location>() {
                @Override
                public void onComplete(@NonNull Task<Location> task) {
                    if (task.isSuccessful() && task.getResult() != null) {
                        onLocationChange(task.getResult());
                        Log.i(TAG, "lat " + task.getResult().getLatitude() + " lng " + task.getResult().getLongitude());
                        Log.i(TAG, "bearing? " + task.getResult().hasBearing());
                    } else {
                        Toast.makeText(MainActivity.this, "Location Not Found!", Toast.LENGTH_SHORT).show();
                    }
                }
            });

}

private void onLocationChange(Location location) {
    //do something
}

Can you show us how you construct the `LocationRequest` (which flags and params) ? — Arseny Levin, Aug 01 '18 at 10:12
@ArsenyLevin I was only calling `getLastLocation` on my `fusedLocationClient`. I changed my code and added _interval_ , _fastestInterval_ and _periority_ parameters to `LocationRequest` but still `hasBearing()` returns false. — mrazizi, Aug 14 '18 at 13:11

score 1 · Answer 1 · answered Aug 01 '18 at 08:27

1

According to documentation

If this location does not have a bearing then 0.0 is returned.

answered Aug 01 '18 at 08:27

code4rox

941
9
34

That's correct but I want to know why the location doesn't have a bearing and if there is a way to handle this problem. – mrazizi Aug 01 '18 at 08:40

score 1 · Accepted Answer · answered Aug 14 '18 at 13:41

I solved my problem using accelerometer and magnetic field sensors. This is the Compass class I use to get bearing of my cell phone:

import android.content.Context;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;

public class Compass implements SensorEventListener {
    private static final String TAG = "Compass";

    public interface CompassListener {
        void onNewAzimuth(float azimuth);
    }

    private CompassListener listener;

    private SensorManager sensorManager;
    private Sensor gsensor;
    private Sensor msensor;

    private float[] mGravity = new float[3];
    private float[] mGeomagnetic = new float[3];
    private float[] R = new float[9];
    private float[] I = new float[9];

    private float azimuth;
    private float azimuthFix;

    public Compass(Context context) {
        sensorManager = (SensorManager) context
                .getSystemService(Context.SENSOR_SERVICE);
        gsensor = sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
        msensor = sensorManager.getDefaultSensor(Sensor.TYPE_MAGNETIC_FIELD);
    }

    public void start() {
        sensorManager.registerListener(this, gsensor,
                SensorManager.SENSOR_DELAY_GAME);
        sensorManager.registerListener(this, msensor,
                SensorManager.SENSOR_DELAY_GAME);
    }

    public void stop() {
        sensorManager.unregisterListener(this);
    }

    public void setAzimuthFix(float fix) {
        azimuthFix = fix;
    }

    public void resetAzimuthFix() {
        setAzimuthFix(0);
    }

    public void setListener(CompassListener l) {
        listener = l;
    }

    @Override
    public void onSensorChanged(SensorEvent event) {
        final float alpha = 0.97f;

        synchronized (this) {
            if (event.sensor.getType() == Sensor.TYPE_ACCELEROMETER) {

                mGravity[0] = alpha * mGravity[0] + (1 - alpha)
                        * event.values[0];
                mGravity[1] = alpha * mGravity[1] + (1 - alpha)
                        * event.values[1];
                mGravity[2] = alpha * mGravity[2] + (1 - alpha)
                        * event.values[2];

                // mGravity = event.values;

                // Log.e(TAG, Float.toString(mGravity[0]));
            }

            if (event.sensor.getType() == Sensor.TYPE_MAGNETIC_FIELD) {
                // mGeomagnetic = event.values;

                mGeomagnetic[0] = alpha * mGeomagnetic[0] + (1 - alpha)
                        * event.values[0];
                mGeomagnetic[1] = alpha * mGeomagnetic[1] + (1 - alpha)
                        * event.values[1];
                mGeomagnetic[2] = alpha * mGeomagnetic[2] + (1 - alpha)
                        * event.values[2];
                // Log.e(TAG, Float.toString(event.values[0]));

            }

            boolean success = SensorManager.getRotationMatrix(R, I, mGravity,
                    mGeomagnetic);
            if (success) {
                float orientation[] = new float[3];
                SensorManager.getOrientation(R, orientation);
                // Log.d(TAG, "azimuth (rad): " + azimuth);
                azimuth = (float) Math.toDegrees(orientation[0]); // orientation
                azimuth = (azimuth + azimuthFix + 360) % 360;
                // Log.d(TAG, "azimuth (deg): " + azimuth);
                if (listener != null) {
                    listener.onNewAzimuth(azimuth);
                }
            }
        }
    }

    @Override
    public void onAccuracyChanged(Sensor sensor, int accuracy) {
    }
}

I calibrated the value by adding 352 to bearing received by onNewAzimuth method of this class and used it in my code:

    Compass compass = new Compass(this);
    Compass.CompassListener cl = new Compass.CompassListener() {

        @Override
        public void onNewAzimuth(float azimuth) {
            // using (360 - (azimuth) + 8) value
        }
    };
    compass.setListener(cl);

FusedLocationProviderClient doesn't have bearing data

2 Answers2