我需要加载一个元框，以便编辑人员在编辑之前首先选择父帖子。但是没有看到我期望的宽元框，正常的编辑页面只是加载：这是wp admin/post new开头的代码。php：

            if ( $post_type == \'news\' && !isset($_GET[\'parent_id\']) ):
                       //checking if parent_id exists on querystring

            //Give them the news meta box only
            add_action(\'add_meta_boxes\', function() { add_meta_box(\'news-parent\', \'Please select the Parent Project for this news:\', \'news_attributes_meta_box\', \'news\', \'normal\', \'high\');});//add wide meta box

              function news_attributes_meta_box($post) {
                  $parentselectbox = wp_dropdown_pages(array(
                  \'post_type\' => \'project\',
                  \'name\' => \'parent_id\',
                  \'show_option_none\' => __(\'(no parent)\'),
                  \'sort_column\'=> \'menu_order,
                  post_title\',
                  \'echo\' => 0
                  ));
                  if ( ! empty($parentselectbox) ) {
                    echo $parentselectbox;
                  } // end empty pages check
                };

            exit;//stop page load after meta box is loaded
            //if chosen, give a move forward link with parent_id on querystring
            endif;