Android 光线传感器的调用

public class TestActivity extends Activity {

    private SensorManager sensorManager;
    //第三步：对传感器信号进行监听
    private SensorEventListener listener = new SensorEventListener() {
        @Override
        public void onSensorChanged(SensorEvent event) {
            //提示当前光照强度
            Toast.makeText(TestActivity.this,
                    "当前光照强度：" + event.values[0] + "勒克斯", Toast.LENGTH_SHORT).show();
        }

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

        }
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //第一步：获取 SensorManager 的实例
        sensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
        //第二步：获取 Sensor 传感器类型
        Sensor sensor = sensorManager.getDefaultSensor(Sensor.TYPE_LIGHT);
        //第四步：注册 SensorEventListener
        sensorManager.registerListener(listener,sensor,SensorManager.SENSOR_DELAY_NORMAL);
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        //传感器使用完毕，释放资源
        if(sensorManager!=null){
            sensorManager.unregisterListener(listener);
        }
    }
}