How do I use the Android Accelerometer?

Question

I'm trying to build an app for reading the values from the accelerometer on my phone, which supports Android 2.1 only.

How do I read from the accelerometer using 2.1-compatible code?

Answer 1

Start with this:

public class yourActivity extends Activity implements SensorEventListener{
 private SensorManager sensorManager;
 double ax,ay,az;   // these are the acceleration in x,y and z axis
 @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        sensorManager=(SensorManager) getSystemService(SENSOR_SERVICE);
        sensorManager.registerListener(this, sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_NORMAL);
   }
   @Override
   public void onAccuracyChanged(Sensor arg0, int arg1) {
   }

   @Override
   public void onSensorChanged(SensorEvent event) {
        if (event.sensor.getType()==Sensor.TYPE_ACCELEROMETER){
            ax=event.values[0];
                    ay=event.values[1];
                    az=event.values[2];
            }
   }
}

Answer 2

This isn't easily explained in a few paragraphs. You should try to read:

• Sensor Overview
• SensorManager description

These show a framework on how to access sensors:

 public class SensorActivity extends Activity implements SensorEventListener {
     private final SensorManager mSensorManager;
     private final Sensor mAccelerometer;

     public SensorActivity() {
         mSensorManager = (SensorManager)getSystemService(SENSOR_SERVICE);
         mAccelerometer = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
     }

     protected void onResume() {
         super.onResume();
         mSensorManager.registerListener(this, mAccelerometer, SensorManager.SENSOR_DELAY_NORMAL);
     }

     protected void onPause() {
         super.onPause();
         mSensorManager.unregisterListener(this);
     }

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

     public void onSensorChanged(SensorEvent event) {
     }
 }

In the onSensorChanged callback you can query the sensor's values through the SensorEvent .

Answer 3

A very good example for accelerometer app.

http://www.techrepublic.com/blog/app-builder/a-quick-tutorial-on-coding-androids-accelerometer/472