Feature: #96526 - PSR-14 Event for modifying page module content

See Issue #96526

Description

A new PSR-14 Event TYPO3\CMS\Backend\Controller\Event\ModifyPageLayoutContentEvent has been introduced which serves as a more powerful and flexible alternative for the now removed hooks $GLOBALS['TYPO3_CONF_VARS']['SC_OPTIONS']['cms/layout/db_layout.php']['drawHeaderHook'] and $GLOBALS['TYPO3_CONF_VARS']['SC_OPTIONS']['cms/layout/db_layout.php']['drawFooterHook'].

Next to the getRequest() and getModuleTemplate() methods does the event feature the usual getter and setter for the header and footer content. It is therefore now possible to not just add additional content to the module, but to also overwrite existing content or to reorder the content.

Example

Registration of the Event in your extensions’ Services.yaml:

MyVendor\MyPackage\Backend\MyEventListener:
  tags:
    - name: event.listener
      identifier: 'my-package/backend/modify-page-module-content'

The corresponding event listener class:

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

class MyEventListener {

    public function __invoke(ModifyPageLayoutContentEvent $event): void
    {
        $event->addHeaderContent('Additional header content');

        $event->setFooterContent('Overwrite footer content');
    }
}

In contrast to the removed hooks, the new event does not provide the PageLayoutController as $parentObject, since getModuleTemplate() has been the only public method, which is now directly included in the event.

Additionally, there were three public properties $id, $pageInfo and $MOD_SETTINGS, which however had already been marked as @internal in TYPO3 v9. If needed, the information can be retrieved from the request directly.

An example to get the current $id:

public function __invoke(ModifyPageLayoutContentEvent $event): void
{
    $id = (int)($event->getRequest()->getQueryParams()['id'] ?? 0);
}

Impact

The new PSR-14 event allows to modify the content of the page module header and footer sections in an efficient and flexible way.