public TypeInterfaceToolWindowRegistrar(Lifetime lifetime,
                                    ToolWindowManager toolWindowManager,
                                    IShellLocks locks,
                                    ISettingsStore settingsStore,
                                    IActionManager actionManager,
                                    IActionBarManager actionBarManager,
                                    IShortcutManager shortcutManager,
                                    TypeInterfaceToolWindowDescriptor toolWindowDescriptor,
                                    ITheming theming,
                                    IThemedIconManager themedIconManager, IColorThemeManager colorThemeManager)
    {
      myLifetime = lifetime;
      myLocks = locks;
      mySettingsStore = settingsStore;
      myActionBarManager = actionBarManager;
      myTheming = theming;
      myThemedIconManager = themedIconManager;
      myColorThemeManager = colorThemeManager;

      myToolWindowClass = toolWindowManager.Classes[toolWindowDescriptor];
      myToolWindowClass.RegisterEmptyContent(
        lifetime,
        lt =>
          {
            var emptyLabel = new RichTextLabel { BackColor = SystemColors.Control, Dock = DockStyle.Fill };
            emptyLabel.RichTextBlock.Add(new RichText("No hierarchies open", new TextStyle(FontStyle.Bold)));
            emptyLabel.RichTextBlock.Add(
              new RichText("Use " + actionManager.GetHowToExecuteAction(shortcutManager, typeof(BrowseTypeHierarchyAction)), TextStyle.Default));
            emptyLabel.RichTextBlock.Add(new RichText("on a type to see hierarchy", TextStyle.Default));
            emptyLabel.RichTextBlock.Parameters = new RichTextBlockParameters(8, ContentAlignment.MiddleCenter);
            return emptyLabel.BindToLifetime(lt);
          });
    }
        public YouTrackExplorerWindowRegistrar(Lifetime lifetime, ToolWindowManager toolWindowManager,
                                        YouTrackExplorerWindowDescriptor descriptor)
        {
            this.lifetime = lifetime;

              toolWindowClass = toolWindowManager.Classes[descriptor];
              toolWindowClass.RegisterEmptyContent(
            lifetime,
            lt =>
            {
              // initialize the default ('empty') content for the tool window
              var label = new RichTextLabel { BackColor = SystemColors.Control, Dock = DockStyle.Fill };
              label.RichTextBlock.Add(new RichText("Nothing Here", new TextStyle(FontStyle.Bold)));
              label.RichTextBlock.Parameters = new RichTextBlockParameters(8, ContentAlignment.MiddleCenter);
              return label.BindToLifetime(lt);
            });
        }