Cakephp 2.0使用flash消息注销

My Logout function is working very well with only return $this->redirect($this->Auth->logout());.

But how could I make a logout function with a Flash message? I tried this function. It doesn't work. I'm always login and it doesn't show me message:(

public function logout() {
    if ($this->Auth->user('logged_in')) {
        $this->Session->setFlash(__('you are logout'), 'default', array('class' => 'alert alert-success'));
        return $this->redirect($this->Auth->logout());
    } else {
        $this->Session->setFlash(__('you aren\'t logout, Please, try again'), 'default', array('class' => 'alert alert-danger'));
    }
}

Inside the documentation says that if you want to create a custom message do by in /app/View/Elements. If you want your personalized message is not the way to go.

in your /app/View/Elements/defaul.ctp

$this->Session->setFlash(__('you are logout'), 'default', array('class' => 'alert alert-success'));

afte in your cont roller

public function logout() {
    if ($this->Auth->user('logged_in')) {
        $this->Session->setFlash('something', 'default');
        return $this->redirect($this->Auth->logout());
    } else {
        $this->Session->setFlash(__('you aren\'t logout, Please, try again'), 'default', array('class' => 'alert alert-danger'));
    }
}

you could also do it through a component