Android Thread: Thực hành code ứng dụng Clock

private val clockHandlerThread: HandlerThread = HandlerThread("Clock-Handler-Thread").apply {
    start()
}
private val clockHandler: Handler by lazy {
    Handler(clockHandlerThread.looper)
}
private val mainHandler: Handler = Handler(Looper.getMainLooper())
private val clockRunnable: Runnable = object : Runnable {
    override fun run() {
        mainHandler.post {
            updateTime()
        }
        clockHandler.postDelayed(this, 1000)
    }
}
private fun startClock() {
    updateTime()
    clockHandler.postDelayed(clockRunnable, 1000)
}