code: public void setEnabledWeekday(int dayOfWeek, boolean enable){
          if(mRepeatMode != REPEAT_WEEKLY)
              return;
  
          if(enable)
              mRepeatSetting = mRepeatSetting | WEEKDAY_MASK[dayOfWeek - 1];
          else
              mRepeatSetting = mRepeatSetting & (~WEEKDAY_MASK[dayOfWeek - 1]);
      }
docs: Enable repeat on a dayOfWeek. Only apply it repeat mode is REPEAT_WEEKLY.
  @param dayOfWeek value of dayOfWeek, take from Calendar obj.
  @param enable Enable this dayOfWeek or not.