protected function get_page_ids()
    {
        $page_ids = array();

        foreach (get_post_types(array(), 'objects') as $post_type) {
            if (! $post_type->has_archive) {
                continue;
            }

            if (! get_option("page_for_{$post_type->name}")) {
                continue;
            }

            $page_ids[$post_type->name] = get_option("page_for_{$post_type->name}");
        }

        return $page_ids;
    }