private void LoadWebResources(IEnumerable <WebResource> results)
        {
            ObservableCollection <EntityTreeViewItem> list = new ObservableCollection <EntityTreeViewItem>();

            var groupList = results
                            .GroupBy(a => a.WebResourceType.Value)
                            .OrderBy(a => a.Key);

            foreach (var group in groupList)
            {
                var groupName = group.First().FormattedValues[WebResource.Schema.Attributes.webresourcetype];

                BitmapImage image = null;

                if (_typeImageMapping.ContainsKey(group.Key))
                {
                    image = _typeImageMapping[group.Key];
                }

                var node = new EntityTreeViewItem(groupName, null, image);

                var nodeEntity = TreeNodeEntity.Convert(group);

                FullfillTreeNode(node, nodeEntity, image);

                list.Add(node);
            }

            ExpandNode(list);

            this.trVWebResources.Dispatcher.Invoke(() =>
            {
                this.trVWebResources.BeginInit();

                this.trVWebResources.ItemsSource = list;

                this.trVWebResources.EndInit();
            });
        }