ZfcUser - flash messages after user registration - zfcuser

Question

I'm trying to add some flash messages after user registered
$sharedManager->attach('ZfcUser\Service\User', 'register.post', function($e) use($serviceManager) {
$user = $e->getParam('user');
$mail = new Mail\ActivateAccount($serviceManager, $user);
$mail->send($user->getEmail());
$flash = $serviceManager->get('ControllerPluginManager')->get('flashMessenger');
$flash->addSuccessMessage('Check your mailbox, please.');
});
However, after I was redirected to login page I didn't see any message. Anybody knows the reason?
There is view helper that displays messages
namespace Application\View\Helper;
use Zend\View\Helper\AbstractHelper;
use Zend\View\Helper\FlashMessenger;
class ShowMessages extends AbstractHelper
{
public function __invoke()
{
$messenger = new FlashMessenger();
$error_messages = $messenger->getErrorMessages();
$messages = $messenger->getSuccessMessages();
$result = '';
if (count($error_messages)) {
foreach ($error_messages as $message) {
$result .= '<p class="alert alert-danger">' . $message . '</p>';
}
}
if (count($messages)) {
foreach ($messages as $message) {
$result .= '<p class="alert alert-success">' . $message . '</p>';
}
}
return $result;
}
}
On other pages flash messages works fine.
Thanks!

Answer 1

I found my mistake. I created new messenger instead of getting it throuhg service locator.
$messenger = new FlashMessenger();
should be
$messenger = $this->sm->getServiceLocator()->get('ControllerPluginManager')->get('flashMessenger');