Question

我正在尝试确定当前区域设置是设置为12或24小时，并相应地设置am / pm。这就是我现在所拥有的，但无论是否设置为24，它都会一直显示上午/下午。

if (DateFormat.is24HourFormat(this))
{
    mHour = mCalendar.get(Calendar.HOUR_OF_DAY);
    int hourOfDay = mHour;
    if (hourOfDay>12)
        views.setTextViewText(R.id.AMPM, "pm");
    if (hourOfDay==12)
        views.setTextViewText(R.id.AMPM, "pm");
    if (hourOfDay<12)
        views.setTextViewText(R.id.AMPM, "am");
}
else {
    views.setTextViewText(R.id.AMPM, "");           
}

Answer 1

不应该是

if (!DateFormat.is24HourFormat(this))

您只想在未设置为24小时格式时分配上午/下午，对吗？

这是一个更紧凑的版本：

if (!DateFormat.is24HourFormat(this)) {
    mHour = mCalendar.get(Calendar.HOUR_OF_DAY);
    int hourOfDay = mHour;
    if (hourOfDay >= 12) {
        views.setTextViewText(R.id.AMPM, "pm");
    } else {
        views.setTextViewText(R.id.AMPM, "am");
    }
} else {
    views.setTextViewText(R.id.AMPM, "");
}

Answer 2

Better solution and whole code sample:

Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(System.currentTimeMillis());

// below, the "hour" and "min" are variables,to which you want to set 
//calendar.For example you can take this values from time picker
calendar.set(Calendar.HOUR_OF_DAY, hour);
calendar.set(Calendar.MINUTE, min);            

is24HourFormat = android.text.format.DateFormat.is24HourFormat(context);

if (is24HourFormat) {
    // if system uses 24hourformat dateFormat will format the calender time according to 24hourformat. "HH" means 24hourformat
    CharSequence setTime = dateFormat.format("HH:mm", calendar);

} else {
    // if system doesnt use 24hourformat dateFormat will format the calender time according to 12hourformat. "hh" means 12hourformat and "a" will show am/pm marker
    CharSequence setTime = dateFormat.format("hh:mm a", calendar);
}

Answer 3

要始终以12小时格式显示AM/PM，而不是以德语显示vorm/nachm，请使用Locale.US作为日期格式：

/**
 * Returns the time in a localized format. The 12-hours format is always displayed with
 * AM/PM (and not for example vorm/nachm in german).
 *
 * @param context the context
 * @return Localized time (15:24 or 3:24 PM).
 */
public static String getTime(Context context, long time) {
    if (android.text.format.DateFormat.is24HourFormat(context)) {
        return new SimpleDateFormat("HH:mm", Locale.US).format(new Date(time));

    } else {
        return new SimpleDateFormat("hh:mm a", Locale.US).format(new Date(time));
    }
}

Answer 4

可能与您无关，但我发现尽管这样做

DateFormat.is24HourFormat(this)

我在TextView中仍然有12个小时的版本。经过几天的玩耍，我发现某些时区，例如印度时区（+5：30 GMT），尽管将24小时制设置为ON，但仍强制使用12小时制。将其更改为Adak（格林尼治标准时间09:00）/美国时区进行了修复。

如何检查系统是12小时还是24小时？

4 个答案: