In extbase, how to access item by another value th

Question

In a custom extbase extension, I need to call a show action, passing it another value than uid (this is a continuation of Use other than primary key as RealURL id_field).

As the value "other than uid" is not resolved, it results in the exception http://wiki.typo3.org/Exception/CMS/1297759968

EDIT: here's the current working (but ugly) Controller code:

/**
 * ItemController
 */
class ItemController extends \TYPO3\CMS\Extbase\Mvc\Controller\ActionController {

    /**
     * itemRepository
     *
     * @var \STUBR\Weiterbildung\Domain\Repository\ItemRepository
     * @inject
     */
    protected $itemRepository = NULL;

    /**
     * action list
     *
     * @return void
     */
    public function listAction(\STUBR\Weiterbildung\Domain\Model\Item $item=null) {
        if (!empty(\TYPO3\CMS\Core\Utility\GeneralUtility::_GET('tx_weiterbildung_pi1'))){
            $this->forward('show');
        }
        $items = $this->itemRepository->findAll();
        $this->view->assign('items', $items);
    }

    /**
     * action show
     *
     * @param \STUBR\Weiterbildung\Domain\Model\Item $item
     * @return void
     */
    public function showAction(\STUBR\Weiterbildung\Domain\Model\Item $item=null) {
       $tx_weiterbildung_pi1_get = \TYPO3\CMS\Core\Utility\GeneralUtility::_GET('tx_weiterbildung_pi1');
       if (!empty($tx_weiterbildung_pi1_get)){
        $dfid = intval($tx_weiterbildung_pi1_get['durchfuehrungId']);
       }
       $items = $this->itemRepository->findByDurchfuehrungId($dfid);
       // helpful:
       //\TYPO3\CMS\Extbase\Utility\DebuggerUtility::var_dump($item);
       $this->view->assign('item', $items[0]);
    }
}

PS here are the 5 lines that could be used in the Repository if the magical method wouldn't work:

//public function findByDurchfuehrungId($dfid) {
//  $query = $this->createQuery();
//  $query->matching($query->equals('durchfuehrungId', $dfid));
//  return $query->execute();
//}

Answer 1

Yes, when you're using actions with model binding in param it will always look for object by field defined as ID - in our case it's always uid, but remember, that you do not need to bind model automatically, as you can retrive it yourself.

Most probably you remember, that some time ago I advised to use <f:link.page additionalParams="{originalUid:myObj.originalUid}"Click here</f:link.page> instead of <f:link.action...>

In that case your show action would look like this:

public function showAction() {
   $item = $this->itemRepository->findByOriginalUid(intval(GeneralUtility::_GET('originalUid')));
   $this->view->assign('item', $item);
}

Where findByOriginalUid should work magically without declaration, but even if it doesn't it's just matter of 5 lines in the repo ;)

Other sample

According to the code you pasted I'd use it rather like this, in this case listAction gets a role of dispatcher for whole plugin:

public function listAction() {
    // access get param in array
    $tx_weiterbildung_pi1_get = \TYPO3\CMS\Core\Utility\GeneralUtility::_GET('tx_weiterbildung_pi1');
    $dfId = intval($tx_weiterbildung_pi1_get['durchfuehrungId']);

    if ($dfId > 0) { // tx_weiterbildung_pi1 exists and is positive, that means you want to go to showAction
        $item = $this->itemRepository->findByDurchfuehrungId($dfId);
        if (!is_null($item)) { // Forward to showAction with found $item
            $this->forward('show', null, null, array('item' => $item));
        }else { // Or redirect to the view URL after excluding single item ID from GET params
            $this->redirectToUri($this->uriBuilder->setArgumentsToBeExcludedFromQueryString(array('tx_weiterbildung_pi1'))->build());
        }
    }

    // No `tx_weiterbildung_pi1` param, so it should be displayed as a listAction

    $items = $this->itemRepository->findAll();
    $this->view->assign('items', $items);
}

/**
 * @param \STUBR\Weiterbildung\Domain\Model\Item $item
 */
public function showAction(\STUBR\Weiterbildung\Domain\Model\Item $item = null) {
    $this->view->assign('item', $item);
}

Your finder should also getFirst() object if possible:

public function findByDurchfuehrungId($DfId) {
    $query = $this->createQuery();
    $query->matching($query->equals('durchfuehrungId', $DfId));
    return $query->execute()->getFirst();
}