Question

When I read the Zend\MVC\Service\ServiceManagerConfig.php in ZF2. I get a problem. Here is the code:

$serviceManager->addInitializer(function ($instance) use ($serviceManager) {
        if ($instance instanceof EventManagerAwareInterface
            && !$instance->getEventManager() instanceof EventManagerInterface
        ) {
            $instance->setEventManager($serviceManager->get('EventManager'));
        }
    });

I know that there is a closure in the method “addInitializer”.But what makes me confused is the parameter “$instance”. It’s a parameter but where is the real value from ? var_dump() of $instance and find that it’s a object,that’s “Zend\ModuleManager\Listener\ServiceListener” ; Where does it come in ?

Answer 1

When you do $sm->get('something'); object will be created using defined factories and then passed to initializers. $instance parameter is that object.

You can see that here