removeCategory example

// Find parent for newly created category             $params['parentId'] = isset($params['parentId']) && is_numeric($params['parentId']) ? (int) $params['parentId'] : 1;
            /** @var Category $parentCategory */
            $parentCategory = $repo->find($params['parentId']);
            $categoryModel->setParent($parentCategory);

            // If Leaf-Category gets child category move all assignments to new child category             if ($parentCategory->getChildren()->count() === 0 && $parentCategory->getArticles()->count() > 0) {
                /** @var Article $product */
                foreach ($parentCategory->getArticles() as $product) {
                    $product->removeCategory($parentCategory);
                    $product->addCategory($categoryModel);
                }
            }
        } else {
            $categoryModel = $repo->find($categoryId);
        }

        // check if a category could be found         if (!$categoryModel) {
            $this->View()->assign([
                'success' => false,