如何在Wooccommerce上添加专栏->；订单后端页面

找不到可以在后端订单列表中添加示例列的工作解决方案。已经尝试过这些（在子主题的函数.php中）：

add_filter('manage_edit-shop_order_columns', 'extra_column');
function extra_column($columns) {
    $columns['title'] = 'Product-x';
    return $columns;
}
add_filter( 'manage_edit-shop_order_columns', 'MY_COLUMNS_FUNCTION' );
function MY_COLUMNS_FUNCTION($columns){
    $new_columns = (is_array($columns)) ? $columns : array();
    unset( $new_columns['order_actions'] );
    //edit this for you column(s)
    //all of your columns will be added before the actions column
    $new_columns['MY_COLUMN_ID_1'] = 'MY_COLUMN_1_TITLE';
//    $new_columns['MY_COLUMN_ID_2'] = 'MY_COLUMN_2_TITLE';
    //stop editing
    $new_columns['order_actions'] = $columns['order_actions'];
    return $new_columns;
}    
add_action( 'manage_shop_order_posts_custom_column', 'MY_COLUMNS_VALUES_FUNCTION', 2 );
function MY_COLUMNS_VALUES_FUNCTION($column){
    global $post;
    $data = get_post_meta( $post->ID );
    //start editing, I was saving my fields for the orders as custom post meta
    //if you did the same, follow this code
    if ( $column == 'MY_COLUMN_ID_1' ) {    
        echo (isset($data['MY_COLUMN_1_POST_META_ID']) ? $data['MY_COLUMN_1_POST_META_ID'] : '');
    }
    if ( $column == 'MY_COLUMN_ID_2' ) {    
        echo (isset($data['MY_COLUMN_2_POST_META_ID']) ? $data['MY_COLUMN_2_POST_META_ID'] : '');
    }
}
add_filter( 'manage_edit-shop_order_columns', 'imarcon_set_custom_column_order_columns');
function imarcon_set_custom_column_order_columns($columns) {
// global $woocommerce;
$nieuwearray = array();
 foreach($columns as $key => $title) {
   if ($key=='billing_address') // in front of the Billing column
     $nieuwearray['order_producten']  = __( 'Products', 'woocommerce' );
    $nieuwearray[$key] = $title;
  }
    return $nieuwearray ;
}

我使用的是WP 4.1.1，启用了儿童主题的Avada 3.7.3，Gravity Forms 1.8.22+一些WooCommerce插件和其他插件。