public void Add(ContextMenuItemModel item)
 {
     if (item != null)
     {
         item.Command = CommandSelection;
         Items.Add(item);
         item.PropertyChanged += Item_PropertyChanged;
     }
 }
        internal String GetSelectedItemId()
        {
            ContextMenuItemModel item = GetSelectedItem();

            if (item != null)
            {
                return(item.id);
            }
            return(null);
        }