Feature: #108819 - RecordFieldPreviewProcessor for custom PreviewRenderers

Description

A new service \TYPO3\CMS\Backend\Preview\RecordFieldPreviewProcessor has been introduced to provide common field rendering helpers for custom content element preview renderers.

Previously, these helper methods were only available in StandardContentPreviewRenderer, which required custom preview renderers to extend that class to access them.

Instead, this service uses the composition-over-inheritance pattern.

The new service provides the following methods:

prepareFieldWithLabel()

Renders a field value with its TCA label prepended in bold.

use TYPO3\CMS\Core\Domain\RecordInterface;

public function prepareFieldWithLabel(
    RecordInterface $record,
    string $fieldName,
): ?string

prepareField()

Renders a processed field value without a label.

use TYPO3\CMS\Core\Domain\RecordInterface;

public function prepareField(
    RecordInterface $record,
    string $fieldName,
): ?string

prepareText()

Processes larger text fields (for example, RTE content) with truncation and HTML stripping.

use TYPO3\CMS\Core\Domain\RecordInterface;

public function prepareText(
    RecordInterface $record,
    string $fieldName,
    int $maxLength = 1500,
): ?string

preparePlainHtml()

Renders plain HTML content with line limiting.

use TYPO3\CMS\Core\Domain\RecordInterface;

public function preparePlainHtml(
    RecordInterface $record,
    string $fieldName,
    int $maxLines = 100,
): ?string

prepareFiles()

Renders thumbnails for file references.

use TYPO3\CMS\Core\Resource\FileReference;

public function prepareFiles(
    iterable|FileReference $fileReferences,
): ?string

linkToEditForm()

Wraps content in an edit link if the user has the appropriate permissions.

use TYPO3\CMS\Core\Domain\RecordInterface;
use Psr\Http\Message\ServerRequestInterface;

public function linkToEditForm(
    string $linkText,
    RecordInterface $record,
    ServerRequestInterface $request,
): string

Impact

Extension developers implementing custom preview renderers can now inject RecordFieldPreviewProcessor to access common field rendering helpers without extending StandardContentPreviewRenderer.

Example usage:

use TYPO3\CMS\Backend\Preview\PreviewRendererInterface;
use TYPO3\CMS\Backend\Preview\RecordFieldPreviewProcessor;
use TYPO3\CMS\Backend\View\BackendLayout\Grid\GridColumnItem;

final class MyCustomPreviewRenderer implements PreviewRendererInterface
{
    public function __construct(
        private readonly RecordFieldPreviewProcessor $fieldProcessor,
    ) {}

    public function renderPageModulePreviewContent(
        GridColumnItem $item,
    ): string {
        $record = $item->getRecord();
        $content = $this->fieldProcessor->prepareFieldWithLabel(
            $record,
            'header',
        );
        $content .= $this->fieldProcessor->prepareFiles($record->get('image'));

        return $content;
    }
}