public function setFlash($key, $value = true, $removeAfterAccess = true)
    {
        $counters = $this->get($this->flashParam, []);
        $counters[$key] = $removeAfterAccess ? -1 : 0;
        $this->data[$key] = $value;
        $this->data[$this->flashParam] = $counters;
    }