public static void SetNullSelectionManager(this GraphicManager manager)
        {
            DefaultSelectionManager oldManager = manager.SelectionManager as DefaultSelectionManager;
            NullSelectionManager    newManager = new NullSelectionManager(manager.FLGView, manager);

            manager.SetSelectionManager(newManager);
        }
        private void SelectionManager_DelayedSelectionChanged(object sender, EventArgs e)
        {
            DefaultSelectionManager manager = sender as DefaultSelectionManager;
            var selectedItems = manager.SelectedItems;

            if (selectedItems.Count > 0)
            {
                foreach (var item in selectedItems)
                {
                }
            }
            DisableGraphBlockInputInternal();
        }