倒转倒计时计时器与小时，分钟和秒

public void reverseTimer(int Seconds, final TextView tv) {

    new CountDownTimer(Seconds * 1000 + 1000, 1000) {

        public void onTick(long millisUntilFinished) {
            int seconds = (int) (millisUntilFinished / 1000);

            int hours = seconds / (60 * 60);
            int tempMint = (seconds - (hours * 60 * 60));
            int minutes = tempMint / 60;
            seconds = tempMint - (minutes * 60);

            tv.setText("TIME : " + String.format("%02d", hours)
                    + ":" + String.format("%02d", minutes)
                    + ":" + String.format("%02d", seconds));
        }

        public void onFinish() {
            tv.setText("Completed");
        }
    }.start();
}

我用kotlin流实现了一个很酷的定时器方法，所以你可以在ViewModel中实现它

    var countDownInit = 30
    fun countDownTimer() = flow<Int> {
    var time = countDownInit
    emit(time)
    while (true){
        time--
        delay(1000L)
        countDownInit = time
        emit(time)
    }
}

然后在你的activity或fragment中像这样调用这个函数

lifecycleScope.launch {
        lifecycle.repeatOnLifecycle(Lifecycle.State.STARTED){
                 viewModel.countDownTimer().collect{time->
                      //and update UI 
                     //and for the finish section you can just use this
                     this.cancel()          
                 }
        }
}

现在在应用程序生命周期的暂停阶段会出现崩溃，你总是有最新的时间

输出:01:30

new CountDownTimer(90000, 1000) {

            public void onTick(long duration) {
                //tTimer.setText("seconds remaining: " + millisUntilFinished / 1000);
                //here you can have your logic to set text to edittext resource id
                // Duration
                long Mmin = (duration / 1000) / 60;
                long Ssec = (duration / 1000) % 60;
                if (Ssec < 10) {
                    tTimer.setText("" + Mmin + ":0" + Ssec);
                } else tTimer.setText("" + Mmin + ":" + Ssec);
            }

            public void onFinish() {
                tTimer.setText("00:00");
            }

        }.start();

只需通过传递秒和textview对象调用下面的函数

public void reverseTimer(int Seconds,final TextView tv){

    new CountDownTimer(Seconds* 1000+1000, 1000) {

        public void onTick(long millisUntilFinished) {
            int seconds = (int) (millisUntilFinished / 1000);
            int minutes = seconds / 60;
            seconds = seconds % 60;
            tv.setText("TIME : " + String.format("%02d", minutes)
                    + ":" + String.format("%02d", seconds));
        }

        public void onFinish() {
            tv.setText("Completed");
        }
    }.start();
}

倒转倒计时计时器与小时，分钟和秒

public void reverseTimer(int Seconds, final TextView tv) {

    new CountDownTimer(Seconds * 1000 + 1000, 1000) {

        public void onTick(long millisUntilFinished) {
            int seconds = (int) (millisUntilFinished / 1000);

            int hours = seconds / (60 * 60);
            int tempMint = (seconds - (hours * 60 * 60));
            int minutes = tempMint / 60;
            seconds = tempMint - (minutes * 60);

            tv.setText("TIME : " + String.format("%02d", hours)
                    + ":" + String.format("%02d", minutes)
                    + ":" + String.format("%02d", seconds));
        }

        public void onFinish() {
            tv.setText("Completed");
        }
    }.start();
}

var futureMinDate = Date()
val sdf = SimpleDateFormat("yyyy-MM-dd", Locale.ENGLISH)
try {
    futureMinDate = sdf.parse("2019-08-22")
} catch (e: ParseException) {
    e.printStackTrace()
}

// Here futureMinDate.time Returns the number of milliseconds since January 1, 1970, 00:00:00 GM
// So we need to subtract the millis from current millis to get actual millis
object : CountDownTimer(futureMinDate.time - System.currentTimeMillis(), 1000) {
    override fun onTick(millisUntilFinished: Long) {
        val sec = (millisUntilFinished / 1000) % 60
        val min = (millisUntilFinished / (1000 * 60)) % 60
        val hr = (millisUntilFinished / (1000 * 60 * 60)) % 24
        val day = ((millisUntilFinished / (1000 * 60 * 60)) / 24).toInt()
        val formattedTimeStr = if (day > 1) "$day days $hr : $min : $sec"
        else "$day day $hr : $min : $sec"
        tvFlashDealCountDownTime.text = formattedTimeStr
    }

    override fun onFinish() {
        tvFlashDealCountDownTime.text = "Done!"
    }
}.start()

传递一个未来日期并将其转换为毫秒。