如何更改UIBarButton项的字体颜色？

let barButtonItem = UIBarButtonItem(title: "按钮", style: .plain, target: self, action: #selector(buttonTapped))
barButtonItem.setTitleTextAttributes([NSAttributedString.Key.foregroundColor: UIColor.red], for: .normal)
barButtonItem.setTitleTextAttributes([NSAttributedString.Key.foregroundColor: UIColor.gray], for: .highlighted)
navigationItem.rightBarButtonItem = barButtonItem

@objc func buttonTapped() {
    print("UIBarButtonItem被点击了")
}