protected virtual void SetupLoadChildrensWorker()
        {
            LoadChildrensWorker.DoWork += (sender, args) =>
            {
                IsLoading = true;

                var results = EmbeddedHierarchyEntry.GetChildren(EmbeddedHierarchyEntry.Item);
                args.Result = results;
            };

            LoadChildrensWorker.RunWorkerCompleted += (sender, args) =>
            {
                var results = args.Result as IEnumerable <object>;
                foreach (var child in results)
                {
                    var childModel = CreateChildrenModel(child);
                    if (childModel != null)
                    {
                        ChildrenModels.Add(childModel);
                    }
                }

                IsLoading = false;
                IsLoaded  = true;
            };
        }
 public VirtualFolderTreeItemViewModel(HierarchyViewModelBase parent, IHierarchy embeddedFolderEntry)
     : base(parent, embeddedFolderEntry)
 {
     ChildrenModels.Add(DummyNode);
 }