尝试使用 ContainerAwareInterface 时未设置容器

Question

在 Symfony 2.8 中，此代码 $this->container 为空。

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');
    }

    ....
}

而我的EntrarYPreregistroFormSubscriber服务配置为：

pmktconcursos.entrarypreregistro.form.subscriber:
    class: PMKT\ConcursosBundle\EventListener\EntrarYPreregistroFormSubscriber
    calls:
        - [ setContainer,[ "@service_container" ] ]

我在$l = $this->container->get('logger'); 遇到异常

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)"}

我错过了什么吗？

Answer 1

您正在制作表单事件侦听器，因此在您的表单类型中您有类似$builder->addEventSubscriber(new EntrarYPreregistroFormSubscriber()); 的内容，因此您可以看到表单事件侦听器的工作方式与常规事件侦听器略有不同。因为是你创建了对象，所以你应该调用setContainer($serviceContainer)。为此，您应该在表单类型中包含服务容器。为此，您应该在控制器中创建表单时将其作为选项传递

// 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,
    ));
}