SensorEventListener接口实现摇一摇功能

private long lastUpdate = 0;
private float last_x, last_y, last_z;
private static final int SHAKE_THRESHOLD = 600;

@Override
public void onSensorChanged(SensorEvent sensorEvent) {
    Sensor mySensor = sensorEvent.sensor;

    if (mySensor.getType() == Sensor.TYPE_ACCELEROMETER) {
        float x = sensorEvent.values[0];
        float y = sensorEvent.values[1];
        float z = sensorEvent.values[2];

        long curTime = System.currentTimeMillis();

        if ((curTime - lastUpdate) > 100) {
            long diffTime = (curTime - lastUpdate);
            lastUpdate = curTime;

            float speed = Math.abs(x + y + z - last_x - last_y - last_z) / diffTime * 10000;

            if (speed > SHAKE_THRESHOLD) {
                if (isForeground(MainActivity.this, "MainActivity")) {
                    Intent intent = new Intent(MainActivity.this, AboutActivity.class);
                    startActivity(intent);
                    finish();
                    overridePendingTransition(R.anim.fade_in, R.anim.fade_out);
                }
            }

            last_x = x;
            last_y = y;
            last_z = z;
        }
    }
}

@Override
public void onAccuracyChanged(Sensor sensor, int i) {

}

SensorManager senSensorManager =(SensorManager)getSystemService(Context.SENSOR_SERVICE);
   Sensor senAccelerometer = senSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
   senSensorManager.registerListener(this, senAccelerometer, SensorManager.SENSOR_DELAY_NORMAL);