public function showOnlyCurrentChildren(ItemInterface $menu)
    {
        $itemIterator = new RecursiveItemIterator($menu->getIterator());

        $iterator = new \RecursiveIteratorIterator($itemIterator, \RecursiveIteratorIterator::SELF_FIRST);
        foreach ($iterator as $menuItem) {
            /** @var \Knp\Menu\MenuItem $menuItem */
            if (!$this->matcher->isCurrent($menuItem) && !$this->matcher->isAncestor($menuItem)) {
                $menuItem->setDisplayChildren(false);
            }
        }
    }