public function executeRead(AgaviParameterHolder $rd)
 {
     $all = (bool) $rd->getParameter('all', false);
     $invisible = (bool) $rd->getParameter('invisible', false);
     $categories = $this->categories->getCategories($all, $invisible);
     $this->setAttributeByRef('categories', $categories);
     return $this->getDefaultViewName();
 }