Change order item custom meta data displayed label and value in WooCommerce Admin orders

Question

In the Woocommerce admin screen, I'm attempting to use the order line meta data to display a button which will open up a new window with the URL of the dropship supplier. I have successfully pulled the supplier URL from the product on order and pushed it to the order line item.

I am able to change the meta data to a button but the consequence of that is the other custom fields which contain the custom options are wiped.

This is the full code which I have added to the functions.php file

add_action( 'woocommerce_checkout_create_order_line_item', 'custom_checkout_create_order_line_item', 20, 4 );
function custom_checkout_create_order_line_item( $item, $cart_item_key, $values, $order ) {
    // Get a product custom field value
    $custom_field_value = get_post_meta( $item->get_product_id(), 'supplier_url', true );
    // Update order item meta
    if ( ! empty( $custom_field_value ) ){
        $item->update_meta_data( '_supplier', $custom_field_value );
    }
}

add_filter('woocommerce_order_item_display_meta_key', 'filter_wc_order_item_display_meta_key', 20, 3 );
function filter_wc_order_item_display_meta_key( $display_key, $meta, $item ) {

    // Change display_key
    if( $meta->key === '_supplier' && is_admin() )
        $display_key = __("Supplier", "woocommerce" );

    return $display_key;    
}

add_filter( 'woocommerce_order_item_display_meta_value', 'change_order_item_meta_value', 20, 3 );
function change_order_item_meta_value( $value, $meta, $item ) {

    // Display supplier meta value as a button
    if( $meta->key === '_supplier' && is_admin() ) {
        $display_value = __('<a class="button" target="_blank" href="'.$value.'">Order</a>', 'woocommerce' );

        return $display_value;    
    }
}

These images show the before and after of using the last block of code.

Before:

After:

Where have I gone wrong with my code and is what i'm trying to achieve possible?

Answer 1

The main mistake is on last function where $display_value should be replaced with just $value and then return $value; should be located at the end before last closing bracket.

I have also revisited all your code:

add_action( 'woocommerce_checkout_create_order_line_item', 'custom_checkout_create_order_line_item', 20, 4 );
function custom_checkout_create_order_line_item( $item, $cart_item_key, $values, $order ) {
    $supplier_url = $values['data']->get_meta( 'supplier_url' ); // Get product custom field value
    
    // add product custom field as custom order item meta data
    if ( ! empty($supplier_url) ){
        $item->update_meta_data( '_supplier', $supplier_url );
    }
}

add_filter('woocommerce_order_item_display_meta_key', 'filter_wc_order_item_display_meta_key', 20, 3 );
function filter_wc_order_item_display_meta_key( $display_key, $meta, $item ) {

    // Change displayed label for specific order item meta key
    if( is_admin() && $item->get_type() === 'line_item' && $meta->key === '_supplier' ) {
        $display_key = __("Supplier", "woocommerce" );
    }
    return $display_key;
}

add_filter( 'woocommerce_order_item_display_meta_value', 'change_order_item_meta_value', 20, 3 );
function change_order_item_meta_value( $value, $meta, $item ) {

    // Change displayed value for specific order item meta key
    if( is_admin() && $item->get_type() === 'line_item' && $meta->key === '_supplier' ) {
        $value = __('<a class="button" target="_blank" href="'.$value.'">Order</a>', 'woocommerce' );
    }
    return $value;
}

Code goes in functions.php file of the active child theme (or active theme). Tested and works.