title: The menu "top-menu" is not defined (Symfony2)
body: <p>I am new to Symfony 2.
  In the project that i was assigned with i am getting an error from Symfony2:</p>
  
  <p><strong>An exception has been thrown during the rendering of a template ("The menu "top-menu" is not defined.") in UnitalMFrontBundle::layout.html.twig at line 96.</strong></p>
  
  <p>In the file "/src/Project/AdminBundle/DataFixtures/Phpcr/LoadMenuData.php" </p>
  
  <p>the class</p>
  
  <pre><code>class LoadMenuData extends ContainerAware implements FixtureInterface, OrderedFixtureInterface
  </code></pre>
  
  <p>has this load() method:</p>
  
  <pre><code>public function load(ObjectManager $dm)
  {
      $basePath = $this-&gt;container-&gt;getParameter('cmf_menu.persistence.phpcr.menu_basepath');
  
      /** @var $menuParent Menu */
      $menuParent = $dm-&gt;find(null, $basePath);
  
      /*
       * TOP MENU
       */
  
      $topMenu = $this-&gt;createMenuNode($dm, $menuParent, 'top-menu', 'Top Menu');
      $topMenu-&gt;setChildrenAttributes(array('class' =&gt; 'header-nav'));
      $dm-&gt;persist($topMenu);
  
      $aboutCompanyPage = $this-&gt;createMenuNode($dm, $topMenu, 'top_about_company', 'About company', null, '/cms/simple/about_us', array('class' =&gt; 'header-nav-li'));
  
      $this-&gt;createMenuNode($dm, $aboutCompanyPage, 'top_about_us', 'About us', null, '/cms/simple/about_us');
      $this-&gt;createMenuNode($dm, $aboutCompanyPage, 'top_history', 'History', null, '/cms/simple/about_us/history');
      $this-&gt;createMenuNode($dm, $aboutCompanyPage, 'top_team', 'Team', null, 'show_collaborator');
  
  
      $this-&gt;createMenuNode($dm, $topMenu, 'top_license', 'Licenses', null, 'show_license', array('class' =&gt; 'header-nav-li'));
      $this-&gt;createMenuNode($dm, $topMenu, 'top_costs', 'Prices', null, 'show_prices', array('class' =&gt; 'header-nav-li'));
      $this-&gt;createMenuNode($dm, $topMenu, 'top_documents', 'Documents', null, 'show_documents', array('class' =&gt; 'header-nav-li'));
      $this-&gt;createMenuNode($dm, $topMenu, 'top_contacts', 'Contacts', null, 'unital_m_front_contacts', array('class' =&gt; 'header-nav-li'));
  
      $dm-&gt;flush();
  }
  </code></pre>
  
  <p>The line 96 in the file "/src/Project/FrontBundle/Resources/views/layout.html.twig" is:</p>
  
  <pre><code>{{ knp_menu_render('top-menu') }}
  </code></pre>
  
  <p>I have searched many places for a solution without result.
  Please advice how to fix this error.</p>