public ICustomNavigationItem GetNavigationItem(Guid itemId, ICustomNavigationItemConfiguration configuration)
        {
            int groupId;

            if (!int.TryParse(HttpUtility.ParseQueryString(configuration.GetStringValue("group", ""))["Group"], out groupId))
            {
                return(null);
            }

            if (groupId <= 0)
            {
                var group = CoreContext.Instance().CurrentGroup;
                if (group != null)
                {
                    groupId = group.ID;
                }
                else
                {
                    return(null);
                }
            }

            string label = configuration.GetStringValue("label", "");

            if (string.IsNullOrEmpty(label))
            {
                label = translationController.GetLanguageResourceValue("configuration_defaultLabel");
            }

            return(new CustomNavigationItem(Id,
                                            () => GetNavigationLabel(groupId, label),
                                            () => GetNavigationUrl(groupId),
                                            (int userId) => GetIsVisible(groupId, userId, Configuration),
                                            () => TEApi.Url.CurrentContext.ApplicationTypeId == Id)
            {
                Configuration = configuration,
                Plugin = this,
                CssClass = "sharepoint-libraries"
            });
        }