public function render()
    {
        parent::render();

        $this->_aViewData['edit'] = $oArticle = oxNew(\OxidEsales\Eshop\Application\Model\Article::class);

        // crossselling
        $this->_createCategoryTree("artcattree");

        // accessoires
        $this->_createCategoryTree("artcattree2");

        $soxId = $this->getEditObjectId();
        if (isset($soxId) && $soxId != "-1") {
            // load object
            $oArticle->load($soxId);

            if ($oArticle->isDerived()) {
                $this->_aViewData['readonly'] = true;
            }
        }

        $iAoc = \OxidEsales\Eshop\Core\Registry::getConfig()->getRequestParameter("aoc");
        if ($iAoc == 1) {
            $oArticleCrossellingAjax = oxNew(\OxidEsales\Eshop\Application\Controller\Admin\ArticleCrosssellingAjax::class);
            $this->_aViewData['oxajax'] = $oArticleCrossellingAjax->getColumns();

            return "popups/article_crossselling.tpl";
        } elseif ($iAoc == 2) {
            $oArticleAccessoriesAjax = oxNew(\OxidEsales\Eshop\Application\Controller\Admin\ArticleAccessoriesAjax::class);
            $this->_aViewData['oxajax'] = $oArticleAccessoriesAjax->getColumns();

            return "popups/article_accessories.tpl";
        }

        return "article_crossselling.tpl";
    }