Android4.0 时间显示12小时制没有显示AM、PM

修改状态栏中控制时间的类HoloClock.java的方法getTimeText()进行修改，判断时间是否为24小时制，若是则直接返回时间若不是则判断是上午还是下午，上午的话添加AM，下午添加PM。

private final CharSequence getTimeText() {
        Context context = getContext();
        int res = DateFormat.is24HourFormat(context)
            ? com.android.internal.R.string.twenty_four_hour_time_format
            : com.android.internal.R.string.twelve_hour_time_format;


        SimpleDateFormat sdf;
        String format = context.getString(res);
        if (!format.equals(mClockFormatString)) {
            // we don't want AM/PM showing up in our statusbar, even in 12h mode
            format = format.replaceAll("a", "").trim();
            mClockFormat = sdf = new SimpleDateFormat(format);
            mClockFormatString = format;
        } else {
            sdf = mClockFormat;
        }
        String result = sdf.format(mCalendar.getTime());
        //2012-9-14 START can not show AM\BM in 12hour
        //return result;
		if(DateFormat.is24HourFormat(context)){
    		return result;
    	}else{
    		String ampmValues;
    		if(mCalendar.get(Calendar.AM_PM) == 0){
    			ampmValues = "AM";
    		}else{
    			ampmValues = "PM";
    		}
    		return result+" "+ampmValues;
    	}
		//2012-9-14 END can not show AM\BM in 12hour
    }

修改锁屏界面控制时间的类DigitalClock.java的方法updateTime()，同上判断时间是否为24小时制和是上午还是下午。

private void updateTime() {
        mCalendar.setTimeInMillis(System.currentTimeMillis());

        CharSequence newTime = DateFormat.format(mFormat, mCalendar);
		
		//2012-9-14 START can not show AM\BM in 12hour
		Context context = getContext();
		String ampmValues;
		if(DateFormat.is24HourFormat(context)){
    		ampmValues = "";
    	}else{
    		if(mCalendar.get(Calendar.AM_PM) == 0){
    			ampmValues = " AM";
    		}else{
    			ampmValues = " PM";
    		}
    	}
		newTime = newTime+ampmValues;
		//2012-9-14 END can not show AM\BM in 12hour
		
        mTimeDisplayBackground.setText(newTime);
        mTimeDisplayForeground.setText(newTime);
        mAmPm.setIsMorning(mCalendar.get(Calendar.AM_PM) == 0);
    }