private void ConceptsTree_MouseDown(object sender, MouseEventArgs e)
        {
            var tn = GetNodeAt(e.X, e.Y);
            if (tn != null)
            {
                CurrentNode = tn as Concept;
            }

            if (conceptContextMenu == null)
            {
                InitializeContextMenu();
            }

            if (EditorObserver.HostEditorMode == Utils.Controls.HtmlEditing.Enums.HtmlEditingToolMode.Design)
            {
                AttachContextMenu();
                contextMenuDetached = false;
            }
            else
            {
                if (!contextMenuDetached)
                {
                    DetachContextMenu();
                    contextMenuDetached = true;
                }
            }
        }
        private void ConceptsTree_AfterSelect(object sender, TreeViewEventArgs e)
        {
            var tn = e.Node;
            if (tn != null)
            {
                CurrentNode = tn as Concept;
            }

            if (conceptContextMenu == null)
            {
                InitializeContextMenu();
            }

            if (EditorObserver.HostEditorMode == Utils.Controls.HtmlEditing.Enums.HtmlEditingToolMode.Design)
            {
                AttachContextMenu();
                contextMenuDetached = false;
            }
            else
            {
                if (!contextMenuDetached)
                {
                    DetachContextMenu();
                    contextMenuDetached = true;
                }
            }
        }