set an alarm to any date and time from datepicker dialog

I try to use datepicker to set the time, and I also built an alarm for that time I set, b开发者_JAVA百科ut the alarm always paly at current time instead of my set time, I don't know why, please help, thanks! here is my code:

You should remove this line:

alarmTime.setTimeInMillis(System.currentTimeMillis()); 

as it set the time of the calendar to current time.