Here's a link to a blog with a solution. Essentially, you stop using the Orientation Sensor and use the Magnetic Field Sensor and Accelerometer Sensor(s) in tandem to get equivalent functionality. It's more work but it does allow you to continue to use a callback to handle orientation changes.
EDIT: Since the original site is no longer available, here's the code example that was previously hosted there:
package com.samplecompass;
import android.app.Activity;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Paint.Style;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.os.Bundle;
import android.view.View;
public class CompassActivity extends Activity implements SensorEventListener {
Float azimut; // View to draw a compass
public class CustomDrawableView extends View {
Paint paint = new Paint();
public CustomDrawableView(Context context) {
super(context);
paint.setColor(0xff00ff00);
paint.setStyle(Style.STROKE);
paint.setStrokeWidth(2);
paint.setAntiAlias(true);
};
protected void onDraw(Canvas canvas) {
int width = getWidth();
int height = getHeight();
int centerx = width/2;
int centery = height/2;
canvas.drawLine(centerx, 0, centerx, height, paint);
canvas.drawLine(0, centery, width, centery, paint);
// Rotate the canvas with the azimut
if (azimut != null)
canvas.rotate(-azimut*360/(2*3.14159f), centerx, centery);
paint.setColor(0xff0000ff);
canvas.drawLine(centerx, -1000, centerx, +1000, paint);
canvas.drawLine(-1000, centery, 1000, centery, paint);
canvas.drawText("N", centerx+5, centery-10, paint);
canvas.drawText("S", centerx-10, centery+15, paint);
paint.setColor(0xff00ff00);
}
}
CustomDrawableView mCustomDrawableView;
private SensorManager mSensorManager;
Sensor accelerometer;
Sensor magnetometer;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mCustomDrawableView = new CustomDrawableView(this);
setContentView(mCustomDrawableView); // Register the sensor listeners
mSensorManager = (SensorManager)getSystemService(SENSOR_SERVICE);
accelerometer = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
magnetometer = mSensorManager.getDefaultSensor(Sensor.TYPE_MAGNETIC_FIELD);
}
protected void onResume() {
super.onResume();
mSensorManager.registerListener(this, accelerometer, SensorManager.SENSOR_DELAY_UI);
mSensorManager.registerListener(this, magnetometer, SensorManager.SENSOR_DELAY_UI);
}
protected void onPause() {
super.onPause();
mSensorManager.unregisterListener(this);
}
public void onAccuracyChanged(Sensor sensor, int accuracy) { }
float[] mGravity;
float[] mGeomagnetic;
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 I[] = new float[9];
boolean success = SensorManager.getRotationMatrix(R, I, mGravity, mGeomagnetic);
if (success) {
float orientation[] = new float[3];
SensorManager.getOrientation(R, orientation);
azimut = orientation[0]; // orientation contains: azimut, pitch and roll
}
}
mCustomDrawableView.invalidate();
}
}
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