uiu-cse/inc/acf/includes/walkers/class-acf-walker-nav-menu-edit.php

<?php

if ( ! defined( 'ABSPATH' ) ) {
	exit; // Exit if accessed directly
}

if ( ! class_exists( 'ACF_Walker_Nav_Menu_Edit' ) ) :

	class ACF_Walker_Nav_Menu_Edit extends Walker_Nav_Menu_Edit {

		/**
		 * Starts the element output.
		 *
		 * Calls the Walker_Nav_Menu_Edit start_el function and then injects the custom field HTML
		 *
		 * @since 5.0.0
		 * @since 5.7.2 Added preg_replace based on https://github.com/ineagu/wp-menu-item-custom-fields
		 *
		 * @param string   $output Used to append additional content (passed by reference).
		 * @param WP_Post  $item   Menu item data object.
		 * @param int      $depth  Depth of menu item. Used for padding.
		 * @param stdClass $args   An object of wp_nav_menu() arguments.
		 * @param int      $id     Current item ID.
		 */
		function start_el( &$output, $item, $depth = 0, $args = array(), $id = 0 ) {

			// vars
			$item_output = '';

			// call parent function
			parent::start_el( $item_output, $item, $depth, $args, $id );

			// inject custom field HTML
			$output .= preg_replace(
			// NOTE: Check this regex from time to time!
				'/(?=<(fieldset|p)[^>]+class="[^"]*field-move)/',
				$this->get_fields( $item, $depth, $args, $id ),
				$item_output
			);
		}


		/**
		 * Get custom fields HTML
		 *
		 * @since 5.0.0
		 * @since 5.7.2 Added action based on https://github.com/ineagu/wp-menu-item-custom-fields
		 *
		 * @param object $item   Menu item data object.
		 * @param int    $depth  Depth of menu item. Used for padding.
		 * @param array  $args   Menu item args.
		 * @param int    $id     Nav menu ID.
		 * @return string
		 */
		function get_fields( $item, $depth, $args = array(), $id = 0 ) {
			ob_start();

			/**
			 * Get menu item custom fields from plugins/themes
			 *
			 * @since 5.7.2
			 *
			 * @param int    $item_id   post ID of menu
			 * @param object $item      Menu item data object.
			 * @param int    $depth     Depth of menu item. Used for padding.
			 * @param array  $args      Menu item args.
			 * @param int    $id        Nav menu ID.
			 */
			do_action( 'wp_nav_menu_item_custom_fields', $item->ID, $item, $depth, $args, $id );
			return ob_get_clean();
		}
	}

endif;