Question

我有一个倒数计时器30秒，进度条工作正常，但当应用程序进入暂停状态计时器仍然有效，但我想当应用程序进入暂停状态计时器和进度条将停止，当恢复应用程序它将从它停止的地方。我怎么能这样做。

这是我的代码： -

@SuppressLint("SetTextI18n")
private void init() {// initialize view controls

    m_timerProgress = (ProgressBar) findViewById(R.id.pb);// finding ID of progressbar

    final TextView tv = (TextView) findViewById(R.id.tv);// finding Id of textview to show timer text
    tv.setText("00:00");// set timer text
    //Initialize a new CountDownTimer instance
    long m_MillisInFuture = 30000;// timer value
    long m_CountDownInterval = 1000;// timer break up
    m_oTimer = new CountDownTimer(m_MillisInFuture, m_CountDownInterval) {
        public void onTick(long millisUntilFinished) {
            @SuppressWarnings("UnusedAssignment") long millis = millisUntilFinished;
            @SuppressLint("DefaultLocale") String hms = String.format("%02d:%02d", TimeUnit.MILLISECONDS.toMinutes(millisUntilFinished),
                    TimeUnit.MILLISECONDS.toSeconds(millisUntilFinished) -
                            TimeUnit.MINUTES.toSeconds(TimeUnit.MILLISECONDS.toMinutes(millisUntilFinished)));
            System.out.println(hms);
            tv.setText(hms);
            //Another one second passed
            //Each second ProgressBar progress counter added one
            m_n_ProgressStatus += 1;
            m_timerProgress.setProgress(m_n_ProgressStatus);
        }

        public void onFinish() {// when timer finished

            Intent i = new Intent(COtpAutoVerificationScreen.this, COtpManualVerificationScreen.class);
            startActivity(i);

        }
    }.start();// start timer
    // retreive progress bar count........
    int progressBarMaximumValue = (int) (m_MillisInFuture / m_CountDownInterval);
    //Set ProgressBar maximum value
    //ProgressBar range (0 to maximum value)
    m_timerProgress.setMax(progressBarMaximumValue);
    //Display the CountDownTimer initial value
    tv.setText(progressBarMaximumValue + "Seconds...");
}

Answer 1

在onPause中取消定时器。使用全局变量来跟踪时间。当计时器运行时，按间隔减少全局变量。

在onResume中使用全局变量作为计时器值启动倒计时器。您的进度条也可以保存最后位置并从那里开始操作。

private long currentMillis=30000;

更改您的init方法以获取一个长参数并将视图初始化移到

之外

private void init( long millis) {

//Initialize a new CountDownTimer instance
long m_MillisInFuture = millis;// timer value
long m_CountDownInterval = 1000;// timer break up
m_oTimer = new CountDownTimer(m_MillisInFuture, m_CountDownInterval) {
    public void onTick(long millisUntilFinished) {
        @SuppressWarnings("UnusedAssignment") long millis = millisUntilFinished;

   long hmsLong=,
                TimeUnit.MILLISECONDS.toSeconds(millisUntilFinished) -                    TimeUnit.MINUTES.toSeconds(TimeUnit.MILLISECONDS.toMinutes(millisUntilFinished));
        @SuppressLint("DefaultLocale") String hms = String.format("%02d:%02d",TimeUnit.MILLISECONDS.toMinutes(millisUntilFinished),hmsLong );
        System.out.println(hms);
        currentMillis=hmsLong;
        tv.setText(hms);
        //Another one second passed
        //Each second ProgressBar progress counter added one
        m_n_ProgressStatus += 1;
        m_timerProgress.setProgress(m_n_ProgressStatus);
    }
         .....
     m_oTimer.start();

然后你的OnPause应该是

        @Override
public void onPause() {
    super.onPause();
    m_oTimer.cancel();
    }

和onResume将是

             @Override
public void onResume() {
    super.onResume();
    init(currentMillis)
    }

这应该做你想要的。

Answer 2

You can achieve this by following steps.
make m_MillisInFuture member variable

public void OnPause(){ 
    m_oTimer.stop();
    m_oTimer = null;
    m_MillisInFuture- = m_n_ProgressStatus*1000;
}

public void onResume(){
    //here create your timer with updated m_MillisInFuture value and start
    startTimer();


}

    private void startTimer(){
        m_oTimer = new CountDownTimer(m_MillisInFuture, m_CountDownInterval) {
        public void onTick(long millisUntilFinished) {
            @SuppressWarnings("UnusedAssignment") long millis = millisUntilFinished;
            @SuppressLint("DefaultLocale") String hms = String.format("%02d:%02d", TimeUnit.MILLISECONDS.toMinutes(millisUntilFinished),
                    TimeUnit.MILLISECONDS.toSeconds(millisUntilFinished) -
                            TimeUnit.MINUTES.toSeconds(TimeUnit.MILLISECONDS.toMinutes(millisUntilFinished)));
            System.out.println(hms);
            tv.setText(hms);
            //Another one second passed
            //Each second ProgressBar progress counter added one
            m_n_ProgressStatus += 1;
            m_timerProgress.setProgress(m_n_ProgressStatus);
        }

        public void onFinish() {// when timer finished

            Intent i = new Intent(COtpAutoVerificationScreen.this, COtpManualVerificationScreen.class);
            startActivity(i);

        }
    }.start();

    }

如何从android中开始使用coundowntimer？

2 个答案: