Symfony 3.0 - not translating according to setLocale() - symfony

Question

In my config.yml if have the following setting
parameters:
locale: en
framework:
translator: { fallbacks: ["%locale%"] }
In my controller I change the locale to French like this:
$request->setLocale('fr')
When I want to translate something in Twig like this{{ 'Something' | trans }} It doesn't show the text in French, even though in my view this {{ dump(app.request.locale) }} gives me fr.
So there is something wrong.
Only when I change the locale in my config.yml to fr like this:
parameters:
locale: fr
then I see the text in French.
Any suggestions?

Answer 1

I ended up creating a localeListener that sets the locale in the session when setting the locale in the controller like this $request->setLocale('fr'). Now my text gets translated in the corresponding locale, but on only after an extra page refresh.
namespace SiteBundle\EventListener;
use Symfony\Component\HttpKernel\Event\GetResponseEvent;
use Symfony\Component\HttpKernel\KernelEvents;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;
class LocaleListener implements EventSubscriberInterface
{
private $defaultLocale;
public function __construct($defaultLocale = 'en')
{
$this->defaultLocale = $defaultLocale;
}
public function onKernelRequest(GetResponseEvent $event)
{
$request = $event->getRequest();
if (!$request->hasPreviousSession()) {
return;
}
// try to see if the locale has been set as a _locale routing parameter
if ($locale = $request->attributes->get('_locale')) {
$request->getSession()->set('_locale', $locale);
} else {
// if no explicit locale has been set on this request, use one from the session
$request->setLocale($request->getSession()->get('_locale', $this->defaultLocale));
}
}
public static function getSubscribedEvents()
{
return array(
// must be registered after the default Locale listener
KernelEvents::REQUEST => array(array('onKernelRequest', 15)),
);
}
}