Cannot attach Events in module init()-method - php

Question

I read about some of the best practices for ZF2. There, it was explained to attach the events from MVC in the init()-Method of the module's Module class:
class Module {
public function getAutoloaderConfig() {
return array(
'Zend\Loader\ClassMapAutoloader' => array(
__DIR__ . '/autoload_classmap.php',
),
);
}
public function init(ModuleManager $moduleManager) {
echo 'init<br>';
$em = $moduleManager->getEventManager();
$em->attach(MvcEvent::EVENT_DISPATCH, array($this, 'onDispatch'));
$em->attach(MvcEvent::EVENT_ROUTE, array($this, 'onRoute'));
}
public function onDispatch(MvcEvent $e){
echo 'onDispatch<br>';
}
...
It results in getting no error, nice. But the event is not caught...
Any ideas? I tried the SharedManager too, but it only worked for the EVENT_DISPATCH ...

Answer 1

Unless for specific cases, it's better to register your events in onBootstrap.
init is for "early events".
I found a link that is quite clear : http://samsonasik.wordpress.com/2013/03/30/zend-framework-2-getting-closer-with-eventmanager/
You can find the order of defaults MVC events in Zend\ModuleManager\Listener\DefaultListenerAggregate::attch :
public function attach(EventManagerInterface $events)
{
$options = $this->getOptions();
$configListener = $this->getConfigListener();
$locatorRegistrationListener = new LocatorRegistrationListener($options);
// High priority, we assume module autoloading (for FooNamespace\Module classes) should be available before anything else
$this->listeners[] = $events->attach(new ModuleLoaderListener($options));
$this->listeners[] = $events->attach(ModuleEvent::EVENT_LOAD_MODULE_RESOLVE, new ModuleResolverListener);
// High priority, because most other loadModule listeners will assume the module's classes are available via autoloading
$this->listeners[] = $events->attach(ModuleEvent::EVENT_LOAD_MODULE, new AutoloaderListener($options), 9000);
if ($options->getCheckDependencies()) {
$this->listeners[] = $events->attach(ModuleEvent::EVENT_LOAD_MODULE, new ModuleDependencyCheckerListener, 8000);
}
$this->listeners[] = $events->attach(ModuleEvent::EVENT_LOAD_MODULE, new InitTrigger($options));
$this->listeners[] = $events->attach(ModuleEvent::EVENT_LOAD_MODULE, new OnBootstrapListener($options));
$this->listeners[] = $events->attach($locatorRegistrationListener);
$this->listeners[] = $events->attach($configListener);
return $this;
}

Answer 2

You'll be better using the shared manager. The example bellow is for disabling layout when we got a xmlHttpRequest and the priority -95 is a key point to make things work.
public function onBootstrap(MvcEvent $e) {
$eventManager = $e->getApplication()->getEventManager();
$moduleRouteListener = new ModuleRouteListener();
$moduleRouteListener->attach($eventManager);
// Hybrid view for ajax calls (disable layout for xmlHttpRequests)
$eventManager->getSharedManager()->attach('Zend\Mvc\Controller\AbstractController', MvcEvent::EVENT_DISPATCH, function(MvcEvent $event){
/**
* #var Request $request
*/
$request = $event->getRequest();
$viewModel = $event->getResult();
if($request->isXmlHttpRequest()) {
$viewModel->setTerminal(true);
}
return $viewModel;
}, -95);
}

Answer 3

See http://akrabat.com/zend-framework-2/module-specific-bootstrapping-in-zf2/
Only found this solution: attach listeners in onBootstrap()-Method in the Module.php class:
...
public function onBootstrap(MvcEvent $e){
echo 'onBootstrap<br>';
$em = $e->getApplication()->getEventManager();
$em->attach(MvcEvent::EVENT_DISPATCH, array($this, 'onDispatch'));
$em->attach(MvcEvent::EVENT_ROUTE, array($this, 'onRoute'));
}
...