Sample create countdown timer

whops.kt

   /**
   *  This sample count down timer 
   *  for auction app when bid start and end
   */
    private lateinit var countDownTimer: CountDownTimer
    private var difference = 0L
    private var isStart = false
    private var startTime = "" // you can chage it with Date
    private var endTime = ""


    private fun yourMethodHere(){
                //using 24 Hours Format
                startTime = "14:00"
                endTime = "16:00"

                //set count down timer
                checkCountDown()
      
                countDownTimer = object : CountDownTimer(difference, 500) {
                    override fun onFinish() {
                      /**
                      * If isStart true countdown start again to check
                      * when auction time ended
                      *
                      */
                        if (isStart) {
                            checkCountDown()
                            if (::countDownTimer.isInitialized) countDownTimer.start() // restart countdown
                        } else {
                          //set count down time text end here
                        }
                    }

                    override fun onTick(millisUntilFinished: Long) {
                        val second = millisUntilFinished / 1000
                        /**
                         * Sample with day
                         * String.format("%02d Day %02d:%02d:%02d",
                        second / (3600 * 24), // Day
                        second / 3600 % 24,  // Hour
                        (second % 3600) / 60, // Minute
                        (second % 60)) // Second
                         */
                        bind.tvCountDownAuction.text = String.format("%02d:%02d:%02d",
                                second / 3600 % 24,
                                (second % 3600) / 60,
                                (second % 60))
                    }
                }
                countDownTimer.start()
    }


   /**
   * This method to check is when bid start or bid end
   */
   @SuppressLint("SimpleDateFormat")
    private fun checkCountDown() {
      
        //Change date format here for example using 24 Hours format
        val simpleDateFormat = SimpleDateFormat("HH:mm")
        val currTime = simpleDateFormat.parse(simpleDateFormat.format(Date()))
        val startTime = simpleDateFormat.parse(startTime)
        val endTime = simpleDateFormat.parse(endTime)

        if (currTime >= startTime) {
            //set false to because is end of auction time
            isStart = false
            //set title countdown auction end timer here
            //update different to calculate start time to end time 
            difference = endTime.time - currTime.time
        } else if (endTime >= currTime) {
          //set true to because is start of auction time
            isStart = true
            //set title countdown auction end timer here
            //update different to calculate start time to end time 
            difference = startTime.time - currTime.time
        }
    }
   
    override fun onDestroy() {
        super.onDestroy()
        countDownTimer.cancel() // cancel countdown on destory or you can put it on onPause
    }