Feature: #98375 - PSR-14 events in Page Module

MyVendor\MyExtension\Listener\ContentUsedOnPage:
  tags:
    - name: event.listener
      identifier: 'my-extension/view/content-used-on-page'

<?php

declare(strict_types=1);

namespace MyVendor\MyExtension\Listener;

use TYPO3\CMS\Backend\View\Event\IsContentUsedOnPageLayoutEvent;

final class ContentUsedOnPage
{
    public function __invoke(IsContentUsedOnPageLayoutEvent $event): void
    {
        // Get the current record from the event.
        $record = $event->getRecord();

        // This code will be your domain logic to indicate if content
        // should be hidden in the page module.
        if ((int)($record['colPos'] ?? 0) === 999
            && !empty($record['tx_myext_content_parent'])
        ) {
            // Flag the current element as not used. Set it to true, if you
            // want to flag it as used and hide it from the page module.
            $event->setUsed(false);
        }
    }
}

MyVendor\MyExtension\Listener\ModifyDatabaseQueryForContent:
  tags:
    - name: event.listener
      identifier: 'my-extension/view/modify-database-query-for-content'

<?php

declare(strict_types=1);

namespace MyVendor\MyExtension\Listener;

use TYPO3\CMS\Backend\View\Event\ModifyDatabaseQueryForContentEvent;
use TYPO3\CMS\Core\Database\Connection;

final class ModifyDatabaseQueryForContent
{
    public function __invoke(ModifyDatabaseQueryForContentEvent $event): void
    {
        // early return if we do not need to react
        if ($event->getTable() !== 'tt_content') {
            return;
        }

        // Retrieve QueryBuilder instance from event
        $queryBuilder = $event->getQueryBuilder();

        // Add an additional condition to the QueryBuilder for the table
        // Note: This is only an example, modify the QueryBuilder instance
        //       here to your needs.
        $queryBuilder = $queryBuilder->andWhere(
            $queryBuilder->expr()->neq(
                'some_field',
                $queryBuilder->createNamedParameter(1, Connection::PARAM_INT)
            )
        );

        // set updated QueryBuilder to event
        $event->setQueryBuilder($queryBuilder);
    }
}

MyVendor\MyExtension\Listener\PageContentPreviewRendering:
  tags:
    - name: event.listener
      identifier: 'my-extension/view/page-content-preview-rendering'

<?php

declare(strict_types=1);

namespace MyVendor\MyExtension\Listener;

use TYPO3\CMS\Backend\View\Event\PageContentPreviewRenderingEvent;

final class PageContentPreviewRendering
{
    public function __invoke(PageContentPreviewRenderingEvent $event): void
    {
        $tableName = $event->getTable();
        $record = $event->getRecord();

        // early return if we do not need to react
        if (
            $tableName !== 'tt_content'
            || (string)($record['CType'] ?? '') !== 'my-content-element'
        ) {
            return;
        }

        // Create custom preview content
        $previewContent = sprintf(
            '<div class="alert alert-notice">No preview available for %s:%s</div>',
            $event->getTable(),
            ($event->getRecord()['uid'] ?? 0)
        );

        // Set (override) preview content with custom content.
        $event->setPreviewContent($previewContent);
    }
}