public new WeekPlannerItem Add(WeekPlannerItem item)
 {
     base.Add(item);
     if (_calendar != null)
     {
         item.Calendar = _calendar;
         _calendar.ResetLayers();
         _calendar.Invalidate();
     }
     return(item);
 }
        public WeekPlannerRow Add(WeekPlannerRow row)
        {
            row.Calendar = _calendar;

            if (row.Items == null)
            {
                row.Items = new WeekPlannerItemCollection(_calendar);
            }
            else
            {
                row.Items.Calendar = _calendar;

                foreach (var item in row.Items)
                {
                    item.Calendar = _calendar;
                }
            }

            base.Add(row);
            _calendar.Invalidate();
            return(row);
        }