TYPO3 10 Viewhelper Class Not Found, Fluid Error

There is some small detail I seem to be missing but I just can't find out what it is...

I get this error:

Error: The ViewHelper "<ugh:example>" could not be resolved. Based on your spelling, the system would load the class "TYPO3\Projectname\ViewHelpers\ExampleViewHelper", however this class does not exist. 

I have my own extension called sitepackage, which works without issues.

In my ext_localconf.php I wrote

$GLOBALS['TYPO3_CONF_VARS']['SYS']['fluid']['namespaces']['ugh'] = ['TYPO3\\Projectname\\ViewHelpers'];

Then there's the directory ViewHelpers inside Classes with the file ExampleViewHelper.php


namespace TYPO3\Projectname\ViewHelpers;

use TYPO3Fluid\Fluid\Core\ViewHelper\AbstractViewHelper;

// etc ... 

I expect it to use like <ugh:example />

What am I missing? Is there something outside of this that I have to do? I'm freaking out about this...



Your global configuration works, yet PHP is not able to find your TYPO3\Projectname\ViewHelpers\ExampleViewHelper.

I suspect that you have a spelling error or your autoloading information is out of date (assuming a composer-based installation, composer dump-autoload updates it) or you forgot to add your namespace to composer.json (see composer docs or a TYPO3 extension example here).

That said, the usual approach is to add ViewHelper namespaces to the Fluid template directly. See

Without composer

Use TYPO3 InstallTool "rebuild autoload information" or similar to build the class autoloading information. I think ext_emconf.php needs to contain the autoloading information, too.