Question

使用日历类确定上午或下午时间。

            Calendar c = Calendar.getInstance(); 
            int seconds = c.get(Calendar.SECOND);
            int minutes = c.get(Calendar.MINUTE);
            int hours = c.get(Calendar.HOUR);
            int years = c.get(Calendar.YEAR);
            int months = 1 + c.get(Calendar.MONTH);
            int days = c.get(Calendar.DAY_OF_MONTH);
            int AM_orPM = c.get(Calendar.AM_PM);

            try{
                if (hours < 12)
                {
                    String PM = "";
                    if (AM_orPM == 1)
                    {
                        PM = "PM";
                    }
                    timestamp.setText("Refreshed on " + months + "-"
                    + days + "-" + years + " " +  hours + ":" + minutes + ":" + seconds + " " + PM);
                    timestamp.setTextSize(17f);
                    timestamp.setTextColor(Color.GREEN);
                }
                else if (hours > 12)
                {
                    String AM = "";
                    if (AM_orPM == 0)
                    {
                        AM = "AM";
                    }
                    hours = hours - 12;
                    timestamp.setText("Refreshed on " + years + "-"
                    + months + "-" + days + " " +  hours + ":" + minutes + ":" + seconds + AM);
                    timestamp.setTextSize(17f);
                    timestamp.setTextColor(Color.GREEN);
                }
            }
            catch (Exception e){}

我想根据当前时间将时间设置为AM或PM。由于某种原因，Calendar.MONTH值也没有给我正确的月份。这是一个关闭因此我必须添加1.只是想知道这是否正常？

int months = 1 + c.get(Calendar.MONTH);

Answer 1

这很正常。因为Calendar.MONTH的索引从0开始。所以你需要+1来获得正确的月份。

Answer 2

确定AM与PM是基于小时的简单计算。这是代码：

String timeString="";
int hour = Calendar.getInstance().get(Calendar.HOUR_OF_DAY);
if (hour == 0) {
    timeString =  "12AM (Midnight)";  
} else if (hour < 12) {
    timeString = hour +"AM";
} else if (hour == 12) {
    timeString = "12PM (Noon)";
} else {
    timeString = hour-12 +"PM";
}

Answer 3

只需查看calendar.get(Calendar.AM_PM) == Calendar.AM

即可

Calendar now = Calendar.getInstance();
if(now.get(Calendar.AM_PM) == Calendar.AM){
   // AM
}else{
   // PM
}

Answer 4

我试过了this，但它不起作用。我必须获取AM_PM值然后进行比较：

int AM_PM = c.get(Calendar.AM_PM);
if(AM_PM == Calendar.AM){
...
...

这是解决方案：

   Calendar c = Calendar.getInstance();
    int AM_PM = c.get(Calendar.AM_PM);

    if(AM_PM == Calendar.AM){
       //AM
    }else{
       //PM
    }

使用日历确定上午或下午日期

4 个答案: