class MainActivity : AppCompatActivity(), SensorEventListener {

    private lateinit var sensorManager: SensorManager

    private var mGravity: Sensor? = null

    private lateinit var sensorX: TextView

    private lateinit var sensorY: TextView

    private lateinit var sensorZ: TextView

    override fun onCreate(savedInstanceState: Bundle?) {

        super.onCreate(savedInstanceState)

        setContentView(R.layout.activity_main)

        sensorManager = getSystemService(Context.SENSOR_SERVICE) as SensorManager

        mGravity = sensorManager.getDefaultSensor(Sensor.TYPE_GRAVITY)

        sensorX = findViewById(R.id.sensorX)

        sensorY = findViewById(R.id.sensorY)

        sensorZ = findViewById(R.id.sensorZ)

    }

    override fun onAccuracyChanged(sensor: Sensor?, accuracy: Int) {

    }

    override fun onSensorChanged(event: SensorEvent) {

        sensorX.text = event.values[0].toString()

        sensorY.text = event.values[1].toString()

        sensorZ.text = event.values[2].toString()

    }

    override fun onResume() {

        super.onResume()

        mGravity.also {

            sensorManager.registerListener(this, it, SensorManager.SENSOR_DELAY_NORMAL)

        }

    }

    override fun onPause() {

        super.onPause()

        sensorManager.unregisterListener(this)

    }

}