public void OnAddExtension()
        {
            DotNetProject p    = CurrentNode.GetParentDataItem(typeof(Project), true) as DotNetProject;
            AddinData     data = AddinData.GetAddinData(p);

            AddinDescription        desc = data.LoadAddinManifest();
            ExtensionSelectorDialog dlg  = new ExtensionSelectorDialog(data.AddinRegistry, null, desc.IsRoot, false);

            if (dlg.Run() == (int)ResponseType.Ok)
            {
                foreach (object ob in dlg.GetSelection())
                {
                    Console.WriteLine("pp s: " + ob);
                }
            }
            dlg.Destroy();
        }