TYPO3 v15 dev-main snapshot ()

Documentation/Changelog/12.0/Feature-96899-NewPSR-14EventModifyGenericBackendMessagesEvent.rst

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+.. include:: /Includes.rst.txt
+
+.. _feature-96899:
+
+=====================================================================
+Feature: #96899 - New PSR-14 event: ModifyGenericBackendMessagesEvent
+=====================================================================
+
+See :issue:`96899`
+
+Description
+===========
+
+A new PSR-14 event :php:`\TYPO3\CMS\Backend\Controller\Event\ModifyGenericBackendMessagesEvent`
+has been introduced. It serves as direct replacement for the now removed hook
+:php:`$GLOBALS['TYPO3_CONF_VARS']['SC_OPTIONS']['t3lib/class.t3lib_befunc.php']['displayWarningMessages']`.
+
+Example
+=======
+
+Registration of an event listener in your extension's :file:`Services.yaml`:
+
+..  code-block:: yaml
+
+    MyVendor\MyPackage\Backend\MyEventListener:
+      tags:
+        - name: event.listener
+          identifier: 'my-package/backend/add-message'
+
+The corresponding event listener class:
+
+..  code-block:: php
+
+    use TYPO3\CMS\Backend\Controller\Event\ModifyGenericBackendMessagesEvent;
+    use TYPO3\CMS\Core\Messaging\FlashMessage;
+
+    class MyEventListener {
+
+        public function __invoke(ModifyGenericBackendMessagesEvent $event): void
+        {
+            // Add a custom message
+            $event->addMessage(new FlashMessage('My custom message'));
+        }
+    }
+
+Impact
+======
+
+The PSR-14 event allows to add or alter messages that are displayed
+in the "About" module (default start module of the TYPO3 Backend).
+
+Extensions such as "Reports" already use this event to display custom
+messages based on the status of the system.
+
+.. index:: Backend, PHP-API, ext:backend