/**
 * @snippet       Add Custom Field @ WooCommerce Quick Edit Product
 * @how-to        Get CustomizeWoo.com FREE
 * @author        Rodolfo Melogli
 * @testedwith    WooCommerce 6
 * @donate $9     https://businessbloomer.com/bloomer-armada/
 */
  
add_action( 'woocommerce_product_quick_edit_start', 'bbloomer_show_custom_field_quick_edit' );
 
function bbloomer_show_custom_field_quick_edit() {
   global $post;
   ?>
   <label>
      <span class="title">Custom field</span>
      <span class="input-text-wrap">
         <input type="text" name="_custom_field" class="text" value="">
      </span>
   </label>
   <br class="clear" />
   <?php
}
 
add_action( 'manage_product_posts_custom_column', 'bbloomer_show_custom_field_quick_edit_data', 9999, 2 );
 
function bbloomer_show_custom_field_quick_edit_data( $column, $post_id ){
    if ( 'name' !== $column ) return;
    echo '<div>Custom field: <span id="cf_' . $post_id . '">' . esc_html( get_post_meta( $post_id, '_custom_field', true ) ) . '</span></div>';
   wc_enqueue_js( "
      $('#the-list').on('click', '.editinline', function() {
         var post_id = $(this).closest('tr').attr('id');
         post_id = post_id.replace('post-', '');
         var custom_field = $('#cf_' + post_id).text();
         $('input[name=\'_custom_field\']', '.inline-edit-row').val(custom_field);
        });
   " );
}
 
add_action( 'woocommerce_product_quick_edit_save', 'bbloomer_save_custom_field_quick_edit' );
 
function bbloomer_save_custom_field_quick_edit( $product ) {
    $post_id = $product->get_id();
    if ( isset( $_REQUEST['_custom_field'] ) ) {
        $custom_field = $_REQUEST['_custom_field'];
        update_post_meta( $post_id, '_custom_field', wc_clean( $custom_field ) );
    }
}