An Android Game Development Framework - Beginning Android Games - page 198

import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
public class AccelerometerHandler implements SensorEventListener {
float accelX;
float accelY;
float accelZ;
public AccelerometerHandler(Context context) {
SensorManager manager=(SensorManager) context
.getSystemService(Context. SENSOR_SERVICE );
if (manager.getSensorList(Sensor. TYPE_ACCELEROMETER ).size() ! = 0) {
Sensor accelerometer=manager.getSensorList(
Sensor. TYPE_ACCELEROMETER ).get(0);
manager.registerListener( this , accelerometer,
SensorManager. SENSOR_DELAY_GAME );
}
}
public void onAccuracyChanged(Sensor sensor, int accuracy) {
// nothing to do here
}
public void onSensorChanged(SensorEvent event) {
accelX=event.values[0];
accelY=event.values[1];
accelZ=event.values[2];
}
public float getAccelX() {
return accelX;
}
public float getAccelY() {
return accelY;
}
public float getAccelZ() {
return accelZ;
}
}
Unsurprisingly, the class implements the SensorEventListener interface that we used in
Chapter 4. The class stores three members by holding the acceleration on each of the three
accelerometers' axes.
The constructor takes a Context , from which it gets a SensorManager instance to set up the
event listening. The rest of the code is equivalent to what we did in Chapter 4. Note that if no
accelerometer is installed, the handler will happily return zero acceleration on all axes throughout
its life. Therefore, we don't need any extra error-checking or exception-throwing code.