Advanced Android: [Lesson #][Step #][description] about android-advanced HOT 2 CLOSED

rather :
class MainActivity : AppCompatActivity() {
private var mSensorManager: SensorManager? = null
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
mSensorManager = this.getSystemService(SENSOR_SERVICE) as SensorManager?
val sensorList: List = mSensorManager.getSensorList(Sensor.TYPE_ALL)
val sensorText = StringBuilder()
for (currentSensor in sensorList) {
sensorText.append(currentSensor.name).append(
System.getProperty("line.separator"))
}
val sensorTextView = findViewById(R.id.sensor_list) as TextView
sensorTextView.text = sensorText

}

from android-advanced.

after debug it is :
class MainActivity : AppCompatActivity() {
private var mSensorManager: SensorManager? = null
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
mSensorManager = this.getSystemService(SENSOR_SERVICE) as SensorManager?
val sensorList = mSensorManager?.getSensorList(Sensor.TYPE_ALL)
val sensorText = StringBuilder()
if (sensorList != null) {
for (currentSensor in sensorList) {
sensorText.append(currentSensor.name).append(
System.getProperty("line.separator"))
}
}
val sensorTextView = findViewById(R.id.sensor_list) as TextView
sensorTextView.text = sensorText

}

from android-advanced.