How to get Direction in Android (Such as North, West)

Question

I am new in Android and I want to get direction according to my camera. How can I get direction information according to my camera? Could you give an idea for this?

Answer 1

Here's what I have so far that's somewhat working for me, values returned are between 0 - 360 but I don't think north is properly calibrated? I'm using this on an LG G Pad running Android 5.0.1

public void onSensorChanged(SensorEvent event) {
    if (event.sensor.getType() == Sensor.TYPE_ACCELEROMETER)
        mGravity = event.values;
    if (event.sensor.getType() == Sensor.TYPE_MAGNETIC_FIELD)
        mGeomagnetic = event.values;
    if (mGravity != null && mGeomagnetic != null) {
        float R[] = new float[9];
        float outR[] = new float[9];
        float I[] = new float[9];

        boolean success = SensorManager.getRotationMatrix(R, I, mGravity, mGeomagnetic);
        if (success) {
            float orientation[] = new float[3];

            SensorManager.remapCoordinateSystem(R, SensorManager.AXIS_X, SensorManager.AXIS_Y, outR);

            SensorManager.getOrientation(outR, orientation);
            azimut = orientation[0];

            float degree = (float)(Math.toDegrees(azimut)+360)%360;

            System.out.println("degree " + degree);

I'm sure there are things I've missed but hopefully this is a decent starting point for others. I reviewed a good number of other questions, comments, etc. to get to this point.