Deprecation: #95222 - Extbase ViewInterface

See forge#95222

Description

To further streamline Fluid view related class inheritance and dependencies, the interface TYPO3\CMS\Extbase\Mvc\View\ViewInterface has been marked as deprecated and will be removed in TYPO3 v12.

Impact

This deprecation has little impact on TYPO3 v11: The interface is kept and still carried around in the Core, no PHP E_USER_DEPRECATED error is triggered.

The interface itself deviates from the casual view related classes only by requiring an implementation of method initializeView() which was never actively used, calling that method will vanish in TYPO3 v12. The second deviation is method setControllerContext(), and class ControllerContext has been marked as deprecated, too.

Affected Installations

The extension scanner will find usages of Extbase ViewInterface as a strong match.

Migration

Some instances may rely on extensions that type hint ViewInterface, especially in the Extbase action controller method initializeView(). The default implementation of that method in TYPO3\CMS\Extbase\Mvc\Controller\ActionController is empty. To simplify compatibility for extensions supporting both TYPO3 v11 and TYPO3 v12, that empty method will be removed in TYPO3 v12, but will still be called if it exists in classes extending ActionController. Extension authors should thus avoid calling parent::initializeView($view) in their implementation of initializeView() to prepare towards TYPO3 v12. Additionally, extension authors should adapt the method signature to avoid a PHP contravariance violation:

// Old:
protected function initializeView(ViewInterface $view)
// New:
protected function initializeView($view)

Apart from that, usages of TYPO3\CMS\Extbase\Mvc\View\ViewInterface should be changed to the more specific TYPO3\CMS\Fluid\View\StandaloneView - usually in non-Extbase related classes, or to the less specific TYPO3Fluid\Fluid\View\ViewInterface.

If using a custom view implementing ViewInterface, keep in mind that auto configuration based on the interface will be dropped in TYPO3 v12, you may have to configure the service in Services.yaml manually.