code: @Override
      public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
          int itemIdx = -1;
          for (int i = 0; i < 7; i++) {
              if (itemIdx == -1 && buttonView == mWeekByDayButtons[i]) {
                  itemIdx = i;
                  mModel.weeklyByDayOfWeek[i] = isChecked;
              }
          }
          updateDialog();
      }
docs: Week repeat by day of week