public void Toggle(AccordionCell selectedItem)
 {
     foreach (var item in _items)
     {
         if (item.Cell != null && item.Cell != selectedItem)
         {
             item.IsSelected = false;
         }
     }
     selectedItem.IsSelected = true;
 }
 public void Toggle(AccordionCell selectedItem)
 {
     foreach (var item in _items)
     {
         if (item.Cell != null && item.Cell != selectedItem)
         {
             item.IsSelected = false;
         }
     }
     selectedItem.IsSelected = true;
 }