RandomNumberGeneratorService.kt

class RandomNumberGeneratorService:Service() {
    private val binder: IBinder = RandomNumberGeneratorServiceBinder()
    private lateinit var handlerThread:HandlerThread
    private lateinit var handler: Handler
    var randomNumber: Int = -1
    private val TAG = RandomNumberGeneratorService::class.java.simpleName
    private lateinit var mNM: NotificationManager
    private val NOTIFICATION = R.string.local_service_started
    private val HANDLER_THREAD_NAME="random_number_generator_thread"
    private lateinit var notificationBuilder: NotificationCompat.Builder
    private var generateRandomNumber = false
    inner class RandomNumberGeneratorServiceBinder : Binder(){
        val service: RandomNumberGeneratorService = this@RandomNumberGeneratorService
    }

    override fun onBind(intent: Intent): IBinder {
        return binder
    }

    override fun onCreate() {
        super.onCreate()
        mNM =  getSystemService(NOTIFICATION_SERVICE) as NotificationManager;
        Log.d(TAG,"service created")
        handlerThread = HandlerThread(HANDLER_THREAD_NAME)
        handlerThread.start()
        handler = Handler(handlerThread.looper)
        handler.post {
            startGeneratingRandomNumber()
        }
        showNotification()
    }

    
    private fun showNotification() {
        val text = getText(R.string.local_service_started)
        // The PendingIntent to launch our activity if the user selects this notification
        val contentIntent = PendingIntent.getActivity(
            this, 0,
            Intent(this, MainActivity::class.java), 0
        )
        // Set the info for the views that show in the notification panel.
        notificationBuilder = NotificationCompat.Builder(this)
            .setSmallIcon(R.mipmap.ic_launcher)  // the status icon
            .setTicker(text)  // the status text
            .setWhen(System.currentTimeMillis())  // the time stamp
            .setContentTitle(getText(R.string.local_service_started))  // the label of the entry
            .setContentText(text)  // the contents of the entry
            .setContentIntent(contentIntent)  // The intent to send when the entry is clicked
        // Send the notification.
        mNM.notify(NOTIFICATION, notificationBuilder.build())
    }

    override fun onDestroy() {
        generateRandomNumber = false
        handler.removeCallbacksAndMessages(null)
        handler.looper.quit()
        handlerThread.quit()
        mNM.cancel(NOTIFICATION)
    }

    override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
        return START_NOT_STICKY
    }
    
    private fun startGeneratingRandomNumber() {
        generateRandomNumber = true
        while (generateRandomNumber){
            Thread.sleep(1000)
            randomNumber = (Math.random()*100).toInt()
        }
    }
}