function update()
 {
     global $ilErr, $ilAccess, $ilObjDataCache;
     if (!$ilAccess->checkAccess('write', '', $this->content_obj->getRefId())) {
         $ilErr->raiseError($this->lng->txt('permission_denied'), $ilErr->MESSAGE);
     }
     $form = $this->initForm(false);
     if ($form->checkInput()) {
         $tmp_grouping = new ilObjCourseGrouping($_REQUEST['obj_id']);
         $tmp_grouping->setTitle($form->getInput('title'));
         $tmp_grouping->setDescription($form->getInput('description'));
         $tmp_grouping->setUniqueField($form->getInput('unique'));
         $tmp_grouping->update();
         ilUtil::sendSuccess($this->lng->txt('settings_saved'), true);
         $this->ctrl->redirect($this, 'listGroupings');
     }
     $form->setValuesByPost();
     $this->edit($form);
 }