Menu/MenuItem.php
public function addNavHeader($name)
    {
        $child = $this->factory->createItem($name);

        $child->setParent($this);
        $child->setCurrentUri($this->getCurrentUri());

        $child->setChildrenAttribute('class', 'nav-header');
        $child->setDisplayLink(false);

        $this->children[$child->getName()] = $child;

        return $child;
    }
public function addNavHeader($name)
    {
        $child = $this->factory->createItem($name);

        $child->setParent($this);
        $child->setCurrentUri($this->getCurrentUri());

        $child->setChildrenAttribute('class', 'nav-header');
        $child->setDisplayLink(false);

        $this->children[$child->getName()] = $child;

        return $child;
    }
Add a divider

@param string $name Nav header label

@return VinceT\AdminBundle\Menu\MenuItem