public TreeOwnerViewModel()
        {
            FillTree();
            var flatListProvider = new DraggableFlatListProvider <BaseTreeItem, CompositeViewModel>(TreeItems);

            DragnDropHandler = new DragnDropHandler <BaseTreeItem, CompositeViewModel>(flatListProvider);
            FlatListProvider = flatListProvider;
        }
 public DragnDropHandler(DraggableFlatListProvider <Node, Parent> itemsProvider)
 {
     _itemsProvider = itemsProvider;
 }