Calculate age from BirthDate

Question

I have DatePicker Dialog, When I select date at that time I want to calculate age it\'s working but when I select date of current year at that time it showing the -1 age instead

Answer 1

This is how I implement in my source code, I tested. Hope that it is useful :

public static int getAge(String dateTime, String currentFormat) {
    SimpleDateFormat dateFormat = new SimpleDateFormat(currentFormat);

    try {
        Date date = dateFormat.parse(dateTime);
        Calendar calendar = Calendar.getInstance();
        calendar.setTime(date);

        int year = calendar.get(Calendar.YEAR);
        int month = calendar.get(Calendar.MONTH);
        int day = calendar.get(Calendar.DAY_OF_MONTH);


        Date currentDate = new Date();
        Calendar currentCalendar = Calendar.getInstance();
        currentCalendar.setTime(currentDate);

        int currentYear = currentCalendar.get(Calendar.YEAR);
        int currentMonth = currentCalendar.get(Calendar.MONTH);
        int currentDay = currentCalendar.get(Calendar.DAY_OF_MONTH);

        int deltaYear = currentYear - year;
        int deltaMonth = currentMonth - month;
        int deltaDay = currentDay - day;

        if (deltaYear > 0) {
            if (deltaMonth < 0) {
                deltaYear --;
            } else if (deltaDay < 0){
                deltaYear --;
            }

            return deltaYear;
        }
    } catch (java.text.ParseException e) {
        e.printStackTrace();
    }

    return 0;
}