限制輸入日期時間

private boolean isDateTrue(int flag) {
		int maxDay=31;
		switch(flag)
		{
		case YEAR:
			year2 = Integer.parseInt(dqrq1_nian.getText().toString());
			if(year2<2100&&year2>1980) return true;
			else return false;
		case MONTH:
			month2 = Integer.parseInt(dqrq1_yue.getText().toString());
			if(month2<=12&&month2>0) return true;
			else return false;
		case DAY:
			day2 = Integer.parseInt(dqrq1_ri.getText().toString());
			if(month2==4||month2==6||month2==9||month2==11) 
				maxDay=30;
			else if(month2==1||month2==3||month2==5||month2==7||month2==8||month2==10||month2==12) 
				maxDay=31;
			else if(month2==2)
			{
				if( ( ((year2%4==0)&&(year2%100==0))||(year2%400==0)  ) )
					maxDay=29;
				else
					maxDay=28;
			}
			if(day2<=maxDay&&day2>0) return true;
			else return false;
		case HOUR:
			hour2 = Integer.parseInt(dqsj1_shi.getText().toString());
			if(hour2<24&&hour2>=0) return true;
			else return false;
		case MINUTE:
			minute2 = Integer.parseInt(dqsj1_fen.getText().toString());
			if(minute2<60&&minute2>=0) return true;
			else return false;
		case SECOND:
			second2 = Integer.parseInt(dqsj1_miao.getText().toString());
			if(second2<60&&second2>=0) return true;
			else return false;
			
		}
		return false;
	}