/// <summary>
        /// GTK-specific command group additions.
        /// </summary>
        partial void AddPlatformCommands()
        {
            // TODO: put strings in resources.
            CheckForUpdatesCommand.MenuParent  = RootCommandGroup.HelpMenuCommand;
            SettingsDialogCommand.MenuParent   = RootCommandGroup.EditMenuCommand;
            SettingsDialogCommand.MenuItemName = "Preferences...";
            SettingsDialogCommand.Weight       = 1.0;
            CommandList.Add(SettingsDialogCommand.CreateSeparator(CommandLocation.Before));

            ExitCommand.MenuItemName              = "Quit";
            ExitCommand.SmallIcon                 = OSImage.Empty;
            ExitCommand.MenuParent                = RootCommandGroup.FileMenuCommand;
            ExitCommand.KeyboardShortcutKey       = "q";
            ExitCommand.KeyboardShortcutModifiers = OSModifierKeys.Menu;
            CommandList.Add(ExitCommand);
            CommandList.Add(ExitCommand.CreateSeparator(CommandLocation.Before));

            ShowOnlineHelpCommand.MenuParent = RootCommandGroup.HelpMenuCommand;
            CommandList.Add(ShowOnlineHelpCommand);
            CommandList.Add(ShowOnlineHelpCommand.CreateSeparator(CommandLocation.After));

            CommandList.Add(AboutApplicationCommand);
            CommandList.Add(AboutApplicationCommand.CreateSeparator(CommandLocation.Before));
        }