Question

我想从timepicker中扣除的小时数+分钟数中减去System.currentTimeMillis()。但是，与转换为System.currentTimeMillis()的小时+分钟相比，MilliSeconds要大得多。

这是我的代码：

// setting my time in milliseconds. hour1 and minute1 taken from timepicker.
app.setTimeMillisDosageTime(TimeUnit.HOURS.toMillis(hour1) + TimeUnit.MINUTES.toMillis(minute1));

我有一个TimerTask，我在减去System.currentTimeMillis。

TimerTask task = new TimerTask()
{
    timeInMillis = app.getTimeMillisDosageTime();
    TimerTask task = new TimerTask()
    {
        @Override
        public void run()
        {
           long ellapsedMillis = timeinMillis - System.currentTimeMillis();
        }
        timer = new Timer(false);
        timer.schedule(task,0,1000);
    }
}

但我的elapsedMillis总是消极的。任何解决方案？

Answer 1

TimeUnit.HOURS.toMillis  
// given number is converted to milliseconds. if you give 1 as input 60*60*1000 is output.
TimeUnit.HOURS.toMillis(1) = 60* 60 * 1000
TimeUnit.MINUTES.toMillis(1) = 60  * 1000 

System.currentTimeMillis() //milli seconds elapsed from January 1, 1970 UTC(coordinated universal time)

但你需要的是将这些小时和分钟设置为当前日期，然后计算从1970年开始经过的秒数。

Calendar chosenTime = Calendar.getInstance();
chosenTime.set(Calendar.HOUR_OF_DAY, selectedHour);
chosenTime.set(Calendar.MINUTE, selectedMinute);

chosenTime.getTime().get(Time)  // This gives you exact seconds that can be substracted from System.currentTimeMillis.

如何从timepicker中取得的Hours + Minutes中减去System.currentTimeMillis（）？

1 个答案: