public function quizCheckLock()
 {
     $quizController = new WpProQuiz_Controller_Quiz();
     echo json_encode($quizController->isLockQuiz($_POST['quizId']));
     exit;
 }
 public static function ajaxQuizCheckLock()
 {
     // workaround ...
     $_POST = $_POST['data'];
     $quizController = new WpProQuiz_Controller_Quiz();
     return json_encode($quizController->isLockQuiz());
 }