public function onDisplayWorkspace(DisplayToolEvent $event)
    {
        $workspace = $event->getWorkspace();

        $content = $this->templating->render(
            'ClarolineCoreBundle:tool:resources.html.twig', [
                'workspace' => $workspace,
                'context' => [
                    'type' => Widget::CONTEXT_WORKSPACE,
                    'data' => $this->serializer->serialize($workspace),
                ],
                'root' => $this->serializer->serialize(
                    $this->resourceRepository->findWorkspaceRoot($workspace)
                ),
            ]
        );

        $event->setContent($content);
        $event->stopPropagation();
    }