1-PostListController.php

<?php

class PostListController extends Controller
{
    private $viewModel;

    public function __construct()
    {
        $this->viewModel = $this->get('view_model.twig');
        $this->on('data.post_list_served', array($this, 'listServed'));
    }

    /**
     * @Route("/blog")
     */
    public function listAction()
    {
        $this->trigger('ui.post_list_requested');

        return new Response($this->viewModel->render('Blog:post_list.html.twig'));
    }

    public function listServed(Event $event)
    {
        $this->viewModel->addSlot('blog_list', $event->getArgument('markup'));
    }

    private function on($name, $call)
    {
        $this->get('event_dispatcher')->addListener($name, $call);
    }

    private function trigger($name, $event = null)
    {
        $this->get('event_dispatcher')->dispatch($name, $event);
    }
}

2-PostModel.php

<?php

class PostModel implements EventSubscriberInterface
{
    private $dispatcher;
    private $repository;
    private $templating;

    public function __construct(EventDispatcherInterface $dispatcher, EntityRepository $repository, BlogTemplateModel $templating)
    {
        $this->dispatcher = $dispatcher;
        $this->repository = $repository;
        $this->templating = $templating;
    }

    public function serveBlogList()
    {
        $posts = $this->repository->findAll();

        $this->dispatcher->dispatcher('data.post_list_served', new GenericEvent(null, array(
            'markup' => $this->templating->renderBlogList($posts),
        )));
    }

    public static function getSubscribedEvents()
    {
        return array(
            'ui.post_list_requested' => 'serveBlogList',
        );
    }
}

3-PostTemplateModel.php

<?php

class PostTemplateModel
{
    private $templating;

    public function __construct(\Twig_Environment $templating)
    {
        $this->templating = $templating;
    }

    public function renderPostList($posts)
    {
        return $this->templating->render('Blog:Post:list.html.twig', array(
            'posts' => $posts,
        ));
    }
}