private function buildFieldList(PhabricatorEditEngineConfiguration $config)
 {
     $viewer = $this->getViewer();
     $engine = $config->getEngine();
     $fields = $engine->getFieldsForConfig($config);
     $form = id(new AphrontFormView())->setUser($viewer)->setAction(null);
     foreach ($fields as $field) {
         $field->setIsPreview(true);
         $field->appendToForm($form);
     }
     $info = id(new PHUIInfoView())->setSeverity(PHUIInfoView::SEVERITY_NOTICE)->setErrors(array(pht('This is a preview of the current form configuration.')));
     $box = id(new PHUIObjectBoxView())->setHeaderText(pht('Form Preview'))->setInfoView($info)->setForm($form);
     return $box;
 }