How do I check if system is 12 or 24 hour?

I am trying to determine if the current locale is set to 12 or 24 hour, and set am/pm accordingly. This is what I have got right now, but it shows am/pm all the time regardless if it is set to 24.

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, "");           
}

Answers


Shouldn't it be

if (!DateFormat.is24HourFormat(this))

You want to assign am/pm only when it is not set to 24 hour format, right?

Here is a more compact version:

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, "");
}

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);
}

To always display AM/PM in 12-hour format and not something like vorm/nachm in german, use Locale.US for the date format:

/**
 * 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));
    }
}

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