Implementing the compass functionality with HERE SDK Navigate edition

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent”>

———— Other UI Components ————

   <androidx.cardview.widget.CardView
        android:layout_width="50dp"
        android:layout_height="50dp"
        android:clickable="true"
        android:onClick="compassClicked"
        app:cardCornerRadius="25dp"
        app:cardPreventCornerOverlap="true"
        app:cardUseCompatPadding="false"
        app:contentPadding="6dp">

        <ImageView
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:src="@drawable/compass_needle" />
    </androidx.cardview.widget.CardView>
</RelativeLayout>

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private boolean isCompassOn = true;

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public void compassClicked(View view) {
        isCompassOn = !isCompassOn;
}

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//For compass UI
private CardView compassFab;
//For sensor configs
private SensorManager mSensorManager;
private Sensor mRotationSensor;
private float[] mRotationMatrix = new float[9];
private float[] mOrientation = new float[3];
//For current location
private GeoCoordinates currentLocation; 
//Additional variable for saving map camera zoom
private int cameraZoom = 0;

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@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_navigation);
compassFab = findViewById(R.id.compassFab);
//sensor configs
mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
// Get a reference to the rotation vector sensor
mRotationSensor = mSensorManager.getDefaultSensor(Sensor.TYPE_ROTATION_VECTOR);
}

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public class NavigationActivity extends AppCompatActivity implements SensorEventListener, MapCameraListener {


mapView.getMapScene().loadScene(MapScheme.NORMAL_DAY, new MapScene.LoadSceneCallback() {
	@Override
           public void onLoadScene(@Nullable MapError mapError) {
		if (mapError == null) {
			——— other functions —————
			mapView.getCamera().addListener(NavigationActivity.this);
		} else {
                    		Log.d(TAG, "Loading map failed: mapErrorCode: " + mapError.name());
                	}
	}	
}

@Override
    protected void onResume() {
        super.onResume();
        // Register the sensor listener
        mSensorManager.registerListener(this, mRotationSensor, SensorManager.SENSOR_DELAY_NORMAL);
    }

@Override
    protected void onPause() {
        super.onPause();
        // Unregister the sensor listener
        mSensorManager.unregisterListener(this);
    }
}

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visualNavigator.setNavigableLocationListener(new NavigableLocationListener() {
            @Override
            public void onNavigableLocationUpdated(@NonNull NavigableLocation currentNavigableLocation) {
		———— other functionality —————
		currentLocation = currentNavigableLocation.originalLocation.coordinates;
            }
        });

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@Override
    public void onMapCameraUpdated(@NonNull MapCamera.State state) {
        // Rotate the compass image
        if (isCompassOn) {
            compassFab.setRotation((float) state.orientationAtTarget.bearing);
        }
    }

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@Override
    public void onSensorChanged(SensorEvent event) {
        if (event.sensor.getType() == Sensor.TYPE_ROTATION_VECTOR) {
            // Convert the rotation vector to a rotation matrix
            SensorManager.getRotationMatrixFromVector(mRotationMatrix, event.values);
            // Convert the rotation matrix to orientation angles
            SensorManager.getOrientation(mRotationMatrix, mOrientation);
            // Convert the azimuth angle to degrees
            float azimuthInRadians = mOrientation[0];
            float azimuthInDegrees = (float) Math.toDegrees(azimuthInRadians);

            // Rotate the map camera and compass image using compass sensor
            if (!isCompassOn) {
                compassFab.setRotation(-azimuthInDegrees);
                GeoOrientationUpdate orientationUpdate = new GeoOrientationUpdate((double) -azimuthInDegrees, 0.0);
                if (currentLocation != null) {
		// please make a check for zoom as it should be one time only 
                    	mapView.getCamera().startAnimation(MapCameraAnimationFactory.flyTo(new GeoCoordinatesUpdate(currentLocation), orientationUpdate, cameraZoom == 0 ? 300 : 0, Duration.ofMillis(1)));
		cameraZoom = 300;
                }
            }
        }
    }

    @Override
    public void onAccuracyChanged(Sensor sensor, int accuracy) {
        // Do nothing
    }

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