下面是我在Kotlin中使用的解决方案

private fun startTimer()
{
    Log.d(TAG, ":startTimer: timeString = '$timeString'")

    object : CountDownTimer(TASK_SWITCH_TIMER, 250)
    {
        override fun onTick(millisUntilFinished: Long)
        {
            val secondsUntilFinished : Long = 
            Math.ceil(millisUntilFinished.toDouble()/1000).toLong()
            val timeString = "${TimeUnit.SECONDS.toMinutes(secondsUntilFinished)}:" +
                    "%02d".format(TimeUnit.SECONDS.toSeconds(secondsUntilFinished))
            Log.d(TAG, ":startTimer::CountDownTimer:millisUntilFinished = $ttlseconds")
            Log.d(TAG, ":startTimer::CountDownTimer:millisUntilFinished = $millisUntilFinished")
        }

        @SuppressLint("SetTextI18n")
        override fun onFinish()
        {
            timerTxtVw.text = "0:00"
            gameStartEndVisibility(true)
        }
    }.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

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();
}

如CountDownTimer的文档所示:

new CountDownTimer(30000, 1000) { onTick(long milliseconds untilfinished) { mTextField。setText("seconds remaining: " + msuntilfinished / 1000); //逻辑来设置EditText可以在这里 ｝ onFinish() { mTextField.setText(“完成了!”); ｝ } .start ();

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();

如果您使用以下代码(如已接受的答案所述)，

new CountDownTimer(30000, 1000) {

    public void onTick(long millisUntilFinished) {
        mTextField.setText("seconds remaining: " + millisUntilFinished / 1000);
       //here you can have your logic to set text to edittext
    }

    public void onFinish() {
        mTextField.setText("done!");
    }

}.start();

如果不仔细清理引用，将导致使用此代码的活动实例的内存泄漏。

使用以下代码

//Declare timer
CountDownTimer cTimer = null;

//start timer function
void startTimer() {
    cTimer = new CountDownTimer(30000, 1000) {
        public void onTick(long millisUntilFinished) {
        }
        public void onFinish() {
        }
    };
    cTimer.start();
}


//cancel timer
void cancelTimer() {
    if(cTimer!=null)
        cTimer.cancel();
}

你需要调用cTtimer.cancel()每当onDestroy()/onDestroyView()在拥有的活动/片段被调用。