在Android中无法使用陀螺仪

Question

我试图在Android中使用陀螺仪 这是我的代码

//on the onCreate method
sensor = (SensorManager) getSystemService(SENSOR_SERVICE);


//the on onSensorChanged method
@Override
public void onSensorChanged(SensorEvent event) {
        Sensor sensor = event.sensor;
        if(sensor.getType() == Sensor.TYPE_GYROSCOPE){
            Log.i("test", "TYPE_GYROSCOPE event");
                }
}

//the onResume method
protected void onResume(){
        super.onResume();
        Sensor Accel = sensor.getDefaultSensor(Sensor.TYPE_GYROSCOPE);
        sensor.registerListener((SensorEventListener) this, Accel, SensorManager.SENSOR_DELAY_FASTEST);
}

但是它不起作用，它永远不会进入Sensor.TYPE_GYROSCOPE状态。