code: @SuppressWarnings("unused")
      public static DatePickerDialog newInstance(OnDateSetListener callback, Calendar initialSelection) {
          DatePickerDialog ret = new DatePickerDialog();
          ret.initialize(callback, initialSelection);
          return ret;
      }
docs: Create a new DatePickerDialog instance with a specific initial selection.
  @param callback         How the parent is notified that the date is set.
  @param initialSelection A Calendar object containing the original selection of the picker.
  (Time is ignored by trimming the Calendar to midnight in the current
  TimeZone of the Calendar object)
  @return a new DatePickerDialog instance