Container not being set when trying to use ContainerAwareInterface - php

Question

With Symfony 2.8, this code $this->container is null.
use Symfony\Component\DependencyInjection\ContainerAwareInterface;
use Symfony\Component\DependencyInjection\ContainerAwareTrait;
class EntrarYPreregistroFormSubscriber implements EventSubscriberInterface, ContainerAwareInterface
{
use ContainerAwareTrait;
public function preSetData(FormEvent $event)
{
$l = $this->container->get('logger');
$l->notice('GOT LOGGER');
}
....
}
And my EntrarYPreregistroFormSubscriber service is configured as:
pmktconcursos.entrarypreregistro.form.subscriber:
class: PMKT\ConcursosBundle\EventListener\EntrarYPreregistroFormSubscriber
calls:
- [ setContainer,[ "#service_container" ] ]
I am getting exception at $l = $this->container->get('logger');
request.CRITICAL: Uncaught PHP Exception Symfony\Component\Debug\Exception\FatalErrorException: "Error: Call to a member function get() on a non-object" at /Users/vmarquez/Proyectos/GrupoPMKT/Promoticket/current/dev/chedraui1607/chedraui1607/src/PMKT/ConcursosBundle/Form/EventListener/EntrarYPreregistroFormSubscriber.php line 30 {"exception":"[object] (Symfony\\Component\\Debug\\Exception\\FatalErrorException(code: 0): Error: Call to a member function get() on a non-object at /Users/vmarquez/Proyectos/GrupoPMKT/Promoticket/current/dev/chedraui1607/chedraui1607/src/PMKT/ConcursosBundle/Form/EventListener/EntrarYPreregistroFormSubscriber.php:30)"}
Am I missing something?

Answer 1

You are making Form Event Listener, so inside your Form Type you have something like $builder->addEventSubscriber(new EntrarYPreregistroFormSubscriber()); so you can see that Form Event Listeners works with a little difference that a regular Event Listener. As it is you who creates the object, so it is you should call setContainer($serviceContainer). To do that you should have service container inside you Form Type. To do that, you should pass it as option while creating your form in controller
// in controller
$object = ...;
$form = $this->createForm(new YourFormType(), $object, array('service_container' => $this->get('service_container')));
// in YourFormType
$listener = new EntrarYPreregistroFormSubscriber();
$listener->setContainer($options['service_container']);
$builder->addEventSubscriber($listener);
...
// in setDefaultOptions method
public function setDefaultOptions(OptionsResolverInterface $resolver)
{
$resolver->setDefaults(array(
...
'service_container' => null,
));
}