public function renderAjax($view, $params = [], $context = null)
    {
        $viewFile = $this->findViewFile($view, $context);

        ob_start();
        ob_implicit_flush(false);

        $this->beginPage();
        $this->head();
        $this->beginBody();
        echo $this->renderFile($viewFile, $params, $context);
        $this->endBody();
        $this->endPage(true);

        return ob_get_clean();
    }