ModifyGenericBackendMessagesEvent
The PSR-14 event
\TYPO3\
allows to add or alter messages that are displayed in the About
module (default start module of the TYPO3 backend).
Extensions such as the EXT:reports system extension use this event to display custom messages based on the system status:
A generic backend message in the about module
Example
EXT:my_extension/Classes/Backend/EventListener/MyEventListener.php
<?php
declare(strict_types=1);
namespace MyVendor\MyExtension\Backend\EventListener;
use TYPO3\CMS\Backend\Controller\Event\ModifyGenericBackendMessagesEvent;
use TYPO3\CMS\Core\Attribute\AsEventListener;
use TYPO3\CMS\Core\Messaging\FlashMessage;
#[AsEventListener(
identifier: 'my-extension/backend/add-message',
)]
final readonly class MyEventListener
{
public function __invoke(ModifyGenericBackendMessagesEvent $event): void
{
// Add a custom message
$event->addMessage(new FlashMessage('My custom message'));
}
}