Sane Custom WP Menu

getMenu.php

<?php 

public function get_menu($menu_name) {
    $locations = get_nav_menu_locations();
    $menu_object = wp_get_nav_menu_object( $locations[ $menu_name ] );
    $array_menu = wp_get_nav_menu_items($menu_object->term_id);
    $menu = array();
    foreach ($array_menu as $m) {
      if (empty($m->menu_item_parent)) {
        $menu[$m->ID] = array();
        $menu[$m->ID]['ID']          =   $m->ID;
        $menu[$m->ID]['title']       =   $m->title;
        $menu[$m->ID]['url']         =   $m->url;
        $menu[$m->ID]['children']    =   array();
      }
    }
    $submenu = array();
    foreach ($array_menu as $m) {
      if ($m->menu_item_parent) {
        $submenu[$m->ID] = array();
        $submenu[$m->ID]['ID']       =   $m->ID;
        $submenu[$m->ID]['title']    =   $m->title;
        $submenu[$m->ID]['url']      =   $m->url;
        $menu[$m->menu_item_parent]['children'][$m->ID] = $submenu[$m->ID];
      }
    }
    return $menu;
  }

nav.php

<?php $menu_items = get_menu('main-menu'); ?>
<nav>
      <ul>
        <?php foreach ($menu_items as $item) : ?>
          <li>
            <a href="<?= $item['url'] ?>" title="<?= $item['title'] ?>"><?= $item['title'] ?></a>
            <?php if( !empty($item['children']) ):?>
            <ul class="sub-menu">
              <?php foreach($item['children'] as $child): ?>
                <li>
                  <a href="<?= $child['url'] ?>" title="<?= $child['title'] ?>"><?= $child['title'] ?></a>
                </li>
              <?php endforeach; ?>
            </ul>
            <?php endif; ?>
          </li>
        <?php endforeach; ?>
     <ul>
</nav>