I'd like to structure a Symfony3 Bundle into submodules.

For this I would like to move the Bundle/Resources folder (with views, config and public) along with the controller classes into a subfolder.

Example with a DemoBundle and the Messages module. The directory should be like this:

+ DemoBundle
    + Directory
    + Posts
    + Messages
       + Controller
           + MessageController.php
       + Resources
           + config
           + public
           + views
               + listing.html.twig

I could move the Controller by making an entry to the routing.yml file like this:

demo-messages:
    resource: "@DemoBundle/Messages/Controller/"
    type:     annotation
    prefix:   /

The Controller now looks like this:

class MessageController extends Controller {
    /**
     * @Route("/messsages", name="Message")
     */
    public function listingAction(Request $request) {
        return $this->render('listing.html.twig', [
            'base_dir' => realpath($this->getParameter('kernel.root_dir').'/..').DIRECTORY_SEPARATOR,
        ]);
    }
}

When I now navigate to this route, I get an error: "Unable to find template". The error says it is still looking in /demo/Resources/views instead of /demo/messages/Resources/views.

Question: Can I somehow tell symfony to look in the folder /demo/messages/Resources/views? Is that possible at all? Or is my template addressing in $this->render(...) wrong?

So far tried the following versions for the template reference:

return $this->render('messages/listing.html.twig', [
                'base_dir' => realpath($this->getParameter('kernel.root_dir').'/..').DIRECTORY_SEPARATOR,
            ]);

Effect: Error: Template not found

~~~

return $this->render('@DemoBundle/Messages/Resources/views/listing.html.twig', [
            'base_dir' => realpath($this->getParameter('kernel.root_dir').'/..').DIRECTORY_SEPARATOR,
        ]);

Works!

The reason I chose this structure over a Bundle for each submodule is that i would like to encapsulate the user interface in this Bundle while i'd like to organize the admin interface in the AdminBundle.