TYPO3 8.7 Extbase generate csv-file - typo3

Question

I try to generate a csv-file in my TYPO3 Extension. I get following error:
1225709595: The Fluid template files "" could not be loaded. (More information)
TYPO3Fluid\Fluid\View\Exception\InvalidTemplateResourceException thrown in file
/usr/local/www/apache24/xx/xx/vendor/typo3fluid/fluid/src/View/TemplatePaths.php in line 719.
25 TYPO3Fluid\Fluid\View\TemplatePaths::resolveFileInPaths(array, "Default", "csv")
My Controller looks like:
$icalView = $this->objectManager->get('TYPO3\\CMS\\Fluid\\View\\StandaloneView');
$extbaseFrameworkConfiguration = $this->configurationManager->getConfiguration(\TYPO3\CMS\Extbase\Configuration\ConfigurationManagerInterface::CONFIGURATION_TYPE_FRAMEWORK);
$icalView->setFormat('csv');
$icalView->setTemplatePathAndFilename('typo3conf/ext/xxx/Resources/Private/Templates/Bestellung/Listbestellungen.txt');
$icalView->assign('xx', $xx);
$icalContent = $icalView->render();
I do have Subfolter "Layout" in ... Bestellung/ and I do have file Default.csv
Same code working in extension in TYPO3 7.6.x - what has changed in 8.7?
Thanks for help!
Martin

Answer 1

Here an snippet how I do it in 8.7 to send an eMail:
As I know you have to set the paths for Template, Layout and Partials also, before you select the template to use
/**
* configurationManager
*
* #var \TYPO3\CMS\Extbase\Configuration\ConfigurationManager
* #inject
*/
protected $configurationManager;
public function sendEmail($template,...)
{
/**
* Generate Email Body
*/
$extbaseFrameworkConfiguration = $this->configurationManager->getConfiguration(ConfigurationManagerInterface::CONFIGURATION_TYPE_FRAMEWORK);
/** #var StandaloneView $emailView */
$emailView = $this->objectManager->get(StandaloneView::class);
$emailView->getRequest()->setControllerExtensionName($controllerExtensionName);
$emailView->getRequest()->setPluginName($pluginName);
$emailView->getRequest()->setControllerName($controllerName);
$emailView->setTemplateRootPaths($extbaseFrameworkConfiguration['view']['templateRootPaths']);
$emailView->setLayoutRootPaths($extbaseFrameworkConfiguration['view']['layoutRootPaths']);
$emailView->setPartialRootPaths($extbaseFrameworkConfiguration['view']['partialRootPaths']);
$emailView->setTemplate('Email/' . ucfirst($template));
$emailView->assignMultiple($variables);
$emailBody = $emailView->render();
}

Answer 2

I solved this by changing the code a little bit and now it is working:
$storage = $this->resourceFactory->getDefaultStorage();
if ($storage === NULL) {
throw new \RuntimeException('Could not get the default storage', 1475590001);
}
/** #var \TYPO3\CMS\Fluid\View\StandaloneView $icalView */
$icalView = $this->objectManager->get('TYPO3\\CMS\\Fluid\\View\\StandaloneView');
$icalView->setFormat('csv');
$templateRootPath[] = \TYPO3\CMS\Core\Utility\GeneralUtility::getFileAbsFileName('EXT:xxx/Resources/Private/Templates/');
$layoutRootPaths[] = \TYPO3\CMS\Core\Utility\GeneralUtility::getFileAbsFileName('EXT:xxx/Resources/Private/Layouts/');
$partialRootPaths[] = \TYPO3\CMS\Core\Utility\GeneralUtility::getFileAbsFileName('EXT:xxx/Resources/Private/Partials/');
$icalView->setLayoutRootPaths($layoutRootPaths);
$icalView->setPartialRootPaths($partialRootPaths);
$icalView->setTemplatePathAndFilename('typo3conf/ext/xxx/Resources/Private/Templates/Bestellung/Listbestellungen.txt');
$icalView->assign('xxx', $xxx);
$icalContent = $icalView->render();
$tempFolder = $storage->getFolder('bestellungencsv');
$tempFile = $storage->createFile('bestellungen_'.$xxx->getUid().'.csv', $tempFolder);
$tempFile->setContents($icalContent);