暂停和恢复计时器而不重置计时器

Question

有什么简单的方法可以让计时器暂停然后再次启动时，它会从暂停的时间恢复？

我查看了其他教程，它们仅在按下暂停按钮两次后重新启动计时器。

我是安卓开发的新手，如果这是一个愚蠢的问题，我很抱歉。

public class Timer extends Fragment {
TextView CurrentDate;
TextView CurrentTime;
Thread ThreadTime;
TextView textTimeStarted;
Button buttonReset;
Button buttonPauseStart;
TextView textElapsedTime;
private Button startButton;
private Button pauseButton;
private TextView timerValue;
long timeInMilliseconds = 0L;
long timeSwapBuff = 0L;
long updatedTime = 0L;
long startTime = 0L;
//runs without a timer by reposting this handler at the end of the runnable
Handler timerHandler = new Handler();
Runnable timerRunnable = new Runnable() {
    @Override
    public void run() {
        long millis = System.currentTimeMillis() - startTime;
        int millisecs = (int) (millis % 1000);
        int seconds = (int) (millis / 1000);
        int minutes = seconds / 60;
        seconds = seconds % 60;
        textElapsedTime.setText(String.format("%d:%02d:%02d", minutes, seconds, millisecs));
        timerHandler.postDelayed(this, 0);
    }
};

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View T = inflater.inflate(R.layout.time_layout, container, false);
    Runnable myRunnableThread = new CountDownRunner();
    ThreadTime = new Thread(myRunnableThread);
    ThreadTime.start();
    ConnecttoXML(T);
    buttonReset = (Button) T.findViewById(R.id.buttonStop);
    buttonReset.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            timerHandler.removeCallbacks(timerRunnable);
            textElapsedTime.setText("");
            textTimeStarted.setText("");
        }
    });
    buttonPauseStart = (Button) T.findViewById(R.id.ButtonStart);
    buttonPauseStart.setText("Start");

    buttonPauseStart.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            buttonPauseStart = (Button) v;
            if (buttonPauseStart.getText().equals("stop")) {
                timerHandler.removeCallbacks(timerRunnable);
                buttonPauseStart.setText("start");
            } else  {
                startTime = System.currentTimeMillis();
                timerHandler.postDelayed(timerRunnable, 0);
                Calendar cs = Calendar.getInstance();
                System.out.println("Current time => " + cs.getTime());
                SimpleDateFormat df = new SimpleDateFormat("HH:mm");
                String formattedDate = df.format(cs.getTime());
                textTimeStarted.setText(formattedDate);
                buttonPauseStart.setText("stop");
            }
        }
    });
    return T;
}
private void ConnecttoXML(View view) {
    CurrentDate = (TextView) view.findViewById(R.id.textCurrentDate);
    textTimeStarted = (TextView) view.findViewById(R.id.textTimeStarted);
    textElapsedTime = (TextView) view.findViewById(R.id.textElapsedTime);
    String currentDate = DateFormat.getDateInstance().format(Calendar.getInstance().getTime());
    CurrentDate.setText(currentDate);
}
public void doWork() {
    getActivity().runOnUiThread(new Runnable() {
        public void run() {
            try {
                CurrentTime = (TextView) getActivity().findViewById(R.id.textCurrentTime);
                Date dt = new Date();
                int hours = dt.getHours();
                int minutes = dt.getMinutes();
                String curTime = hours + ":" + minutes;
                CurrentTime.setText(curTime);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    });
}

public class CountDownRunner implements Runnable {
    @Override
    public void run() {
        while (!Thread.currentThread().isInterrupted()) {
            try {
                doWork();
                Thread.sleep(1000); // Pause of 1 Second
            } catch (InterruptedException e) {
                Thread.currentThread().interrupt();
            } catch (Exception e) {
            }
        }
    }
}
}

Answer 1

不，对于处理程序，您只能设置时间然后取消它，但我看不出这会如何帮助您，因为您正在运行 postDelayat at 0，基本上尽可能快地更新 UI 中的计时器。

如果要暂停计时器，则必须保存经过的时间而不是开始时间，并具有开始/停止和重置按钮。

这是我发现的将暂停添加到计时器的最简单方法：

buttonPauseStart.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            buttonPauseStart = (Button) v;
            if (buttonPauseStart.getText().equals("stop")) {
                elapsedTime = System.currentTimeMillis() - startTime;
                timerHandler.removeCallbacks(timerRunnable);
                buttonPauseStart.setText("start");
            } else  {
                startTime = System.currentTimeMillis() - elapsedTime;
                timerHandler.postDelayed(timerRunnable, 0);
                Calendar cs = Calendar.getInstance();
                System.out.println("Current time => " + cs.getTime());
                SimpleDateFormat df = new SimpleDateFormat("HH:mm");
                String formattedDate = df.format(cs.getTime());
                textTimeStarted.setText(formattedDate);
                buttonPauseStart.setText("stop");
            }
        }
    });