android date picker fragment

DatePickerFragment.java

    private class DatePickerFragment extends DialogFragment implements DatePickerDialog.OnDateSetListener {

        @Override
        public Dialog onCreateDialog(Bundle savedInstanceState) {
            int year = calendar.get(Calendar.YEAR);
            int month = calendar.get(Calendar.MONTH);
            int dayOfMonth = calendar.get(Calendar.DAY_OF_MONTH);

            return new DatePickerDialog(getActivity(), this, year, month, dayOfMonth);
        }

        @Override
        public void onDateSet(DatePicker view, int year, int monthOfYear, int dayOfMonth) {
            calendar.set(Calendar.YEAR, year);
            calendar.set(Calendar.MONTH, monthOfYear);
            calendar.set(Calendar.DAY_OF_MONTH, dayOfMonth);
            //do some stuff
        }
    }