To get a week number of a specific date use the Calendar.Week_of_year. To get the week numbers of a certain month run through each day of the month. You can do something like this, calling the function for a the specific month and year and String[] in return with the week number for each day.
Tag: calendar
How To Check The Weekday In Android
If you want to check for a specific day in the week use the Calendar.Day_of_Week. Calendar rightNow = Calendar.getInstance(); if (rightNow.get(Calendar.DAY_OF_WEEK) == Calendar.FRIDAY){ //do some stuff here } RightNow is todays date. Then it check if the date is a friday.