/**
  * The logic to set the display of the valid_X_field date list field.
  *
  * @param \MUtil_Model_ModelAbstract $model The round model
  * @param string $fieldName The valid_X_field to set
  * @param string $source The date list source as defined by this object
  * @param int $roundId Optional a round id
  * @param string $language   (ISO) language string
  * @param boolean $validAfter True if it concerns _valid_after_ dates
  */
 protected function setDateListFor(\MUtil_Model_ModelAbstract $model, $fieldName, $source, $roundId, $language, $validAfter)
 {
     $dateOptions = $this->getDateOptionsFor($source, $roundId, $language, $validAfter);
     switch (count($dateOptions)) {
         case 0:
             $model->del($fieldName, 'label');
             break;
         case 1:
             $model->set($fieldName, 'elementClass', 'exhibitor');
             // Intentional fall through
         // Intentional fall through
         default:
             $model->set($fieldName, 'multiOptions', $dateOptions);
             break;
     }
 }