WooCommerce根据添加的自定义标题字段过滤管理员订单列表

Question

In WooCommerce, I have added a new custom column 'Language' in my admin order list with custom values 'Japanese' or 'Non Japanese'.

How should I add filter option for Japanese language and Non Japanese language.

I added a filter drop down using below code:

add_action( 'restrict_manage_posts', 'wpse45436_admin_posts_filter_restrict_manage_posts' );
function wpse45436_admin_posts_filter_restrict_manage_posts(){
    global $post_type;
    if( $post_type == 'shop_order' ) {
        //change this to the list of values you want to show
        //in 'label' => 'value' format
        $values = array(
            'Japanese' => 'Japanese', 
            'Non Japanese' => 'Non Japanese',
        );
        ?>
        <select name="ADMIN_FILTER_FIELD_VALUE">
        <option value=""><?php _e('Filter By ', 'wose45436'); ?></option>
        <?php
            $current_v = isset($_GET['ADMIN_FILTER_FIELD_VALUE'])? $_GET['ADMIN_FILTER_FIELD_VALUE']:'';
            foreach ($values as $label => $value) {
                printf (
                    '<option value="%s"%s>%s</option>',
                    $value,
                    $value == $current_v? ' selected="selected"':'',
                    $label
                );
            }
        ?>
        </select>
        <?php
    }
}

I also added some code for filtering order list but its not working, here is my code:

add_action( 'pre_get_posts', 'apply_my_custom_product_filters' );
function apply_my_custom_product_filters( $query ) {

    global $pagenow;
    $paged = (get_query_var('paged')) ? get_query_var('paged') : 1; 
    if ( $query->is_admin && $pagenow == 'edit.php' && isset( $_GET['ADMIN_FILTER_FIELD_VALUE'] ) && $_GET['ADMIN_FILTER_FIELD_VALUE'] != '' && $_GET['post_type'] == 'shop_order' ) {

       $meta_key_query = array(
          array(
              'meta_key'     => 'order_add_language',
              'value'   => esc_attr( $_GET['ADMIN_FILTER_FIELD_VALUE'] ),
              'compare' => '=',
          ),
          'posts_per_page' => 10,
          'paged' => $paged,
      );

      $query->set( 'meta_query', $meta_key_query );
    }
}

Answer 1

This is wrong in your meta_key_query.You can try this code.

add_action( 'pre_get_posts', 'apply_my_custom_product_filters' );
function apply_my_custom_product_filters( $query ) {

    global $pagenow;
    $paged = (get_query_var('paged')) ? get_query_var('paged') : 1; 
    if ( $query->is_admin && $pagenow == 'edit.php' && isset( $_GET['ADMIN_FILTER_FIELD_VALUE'] ) && $_GET['ADMIN_FILTER_FIELD_VALUE'] != '' && $_GET['post_type'] == 'shop_order' ) {

      $meta_key_query = array(
        array(
          'meta_key'     => 'order_add_language',
          'value'   => esc_attr( $_GET['ADMIN_FILTER_FIELD_VALUE'] ),
        )
      );
      $query->set( 'meta_query', $meta_key_query );

    }

}