.. include:: /Includes.rst.txt

.. _feature-97454-1657327622:

===================================================================
Feature: #97454 - PSR-14 events for modifying link browser behavior
===================================================================

See :issue:`97454`

Description
===========

Two new PSR-14 events :php:`\TYPO3\CMS\Backend\Controller\Event\ModifyLinkHandlersEvent` and
:php:`\TYPO3\CMS\Backend\Controller\Event\ModifyAllowedItemsEvent` have been introduced which
serve as a direct replacement for the now removed
:php:`$GLOBALS['TYPO3_CONF_VARS']['SC_OPTIONS']['LinkBrowser']['hooks']`
:doc:`hooks <../12.0/Breaking-97454-RemoveLinkBrowserHooks>`.

The :php:`ModifyLinkHandlersEvent` is triggered before link handlers are
executed, allowing listeners to modify the set of handlers that will be used.
It is the direct replacement for the method :php:`modifyLinkHandlers()` in the
LinkBrowser hook.

The :php:`ModifyAllowedItemsEvent` can be used to dynamically modify the
allowed link types. It is the direct replacement for the method :php:`modifyAllowedItems()`
in the LinkBrowser hook.

..  seealso::
    *   :ref:`breaking-97454-1657327622`
    *   :ref:`t3coreapi:modifyLinkHandlers`
    *   :ref:`t3coreapi:ModifyLinkHandlersEvent`
    *   :ref:`t3coreapi:ModifyAllowedItemsEvent`

Example
=======

Registration of the event in your extension's :file:`Services.yaml`:

..  code-block:: yaml

    MyVendor\MyPackage\MyEventListener:
      tags:
        - name: event.listener
          identifier: 'my-package/recordlist/link-handlers'

The corresponding event listener class:

..  code-block:: php

    use TYPO3\CMS\Backend\Controller\Event\ModifyLinkHandlersEvent;

    final class MyEventListener
    {
        public function __invoke(ModifyLinkHandlersEvent $event): void
        {
            $handler = $event->getLinkHandler('url.');
            $handler['label'] = 'My custom label';
            $event->setLinkHandler('url.', $handler);
        }
    }

Impact
======

It's now possible to modify link handlers behavior using the new PSR-14
:php:`ModifyLinkHandlersEvent` and :php:`ModifyAllowedItemsEvent`.

.. index:: Backend, PHP-API, ext:backend