androidL如何重置计时器(androidL how to reset a timer)

 我正在学习使用计时器，并按照http://examples.javacodegeeks.com/android/core/os/handler/android-timer-example/中的示例进行操作。 
 
 我希望以一种方式实现，当用户按下按钮时计时器将启动，当用户的手关闭时停止，所以我编码如下： 
 
 代码： 
 
button_right.setOnTouchListener( new View.OnTouchListener() 
{
    @Override
    public boolean onTouch(View arg0, MotionEvent event) 
    {
        if(event.getAction()==MotionEvent.ACTION_DOWN )
        {
            startTime = SystemClock.uptimeMillis();
            customHandler.postDelayed(updateTimerThread, 0);



        if((event.getAction()==MotionEvent.ACTION_UP || event.getAction()==MotionEvent.ACTION_CANCEL))
        {
            timeSwapBuff += timeInMilliseconds;
            customHandler.removeCallbacks(updateTimerThread);
        }
        return false;
    }
});  



// setting timer
private Runnable updateTimerThread = new Runnable() 
{
    public void run() 
    {
        timeInMilliseconds = SystemClock.uptimeMillis() - startTime;
        updatedTime = timeSwapBuff + timeInMilliseconds;

        int secs = (int) (updatedTime / 1000);
        int mins = secs / 60;
        secs = secs % 60;
        int milliseconds = (int) (updatedTime % 1000);
        tv_timing.setText("" + mins + ":" + String.format("%02d", secs) + ":" + String.format("%03d", milliseconds));
        customHandler.postDelayed(this, 0);
    }
};      
 
 问题： 
 
 一切正常，定时器将在用户按下按钮时启动，在保持时保持运行并在手动关闭时停止。 然而，我发现当用户再次按下按钮时，计时器从上次停止的位置开始，而不是在计算时间之前重置为0。 
 
 如果使用此代码，如何修改以使计时器重置为0，以便在再次按下按钮时重新计数？ 谢谢！！ 

I am learning to use a timer, and follow the example in http://examples.javacodegeeks.com/android/core/os/handler/android-timer-example/. 
 
I would like to implement in a way that the timer will start off when the user is pressing the button and stop when the user's hand is off, so I have coded as follows:
 
Codes:
 
button_right.setOnTouchListener( new View.OnTouchListener() 
{
    @Override
    public boolean onTouch(View arg0, MotionEvent event) 
    {
        if(event.getAction()==MotionEvent.ACTION_DOWN )
        {
            startTime = SystemClock.uptimeMillis();
            customHandler.postDelayed(updateTimerThread, 0);



        if((event.getAction()==MotionEvent.ACTION_UP || event.getAction()==MotionEvent.ACTION_CANCEL))
        {
            timeSwapBuff += timeInMilliseconds;
            customHandler.removeCallbacks(updateTimerThread);
        }
        return false;
    }
});  



// setting timer
private Runnable updateTimerThread = new Runnable() 
{
    public void run() 
    {
        timeInMilliseconds = SystemClock.uptimeMillis() - startTime;
        updatedTime = timeSwapBuff + timeInMilliseconds;

        int secs = (int) (updatedTime / 1000);
        int mins = secs / 60;
        secs = secs % 60;
        int milliseconds = (int) (updatedTime % 1000);
        tv_timing.setText("" + mins + ":" + String.format("%02d", secs) + ":" + String.format("%03d", milliseconds));
        customHandler.postDelayed(this, 0);
    }
};      
 
Questions:
 
Everything works fine, and the timer will start when the user presses the button, keep running when holding and stop when hand is off. Yet I discover that when the user presses the button again, the timer start off from where it stops last time instead of resetting to 0 before counting time.
 
If using this code, how could it be modified such that the timer is reset to 0 so as to count all over again when the button is being pressed again? Thanks!!

原文：https://stackoverflow.com/questions/19211581