如何使UIToolbar字体与UINavigation Controller匹配？

import UIKit

class MyViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()

        let toolbar = UIToolbar()
        toolbar.barStyle = navigationController?.navigationBar.barStyle
        toolbar.isTranslucent = navigationController?.navigationBar.isTranslucent
        toolbar.tintColor = navigationController?.navigationBar.tintColor
        toolbar.backgroundColor = navigationController?.navigationBar.backgroundColor

        // 设置toolbar的items
        let toolbarItems = [UIBarButtonItem(barButtonSystemItem: .flexibleSpace, target: nil, action: nil), UIBarButtonItem(title: "Example", style: .plain, target: self, action: #selector(exampleButtonTapped))]
        toolbar.setItems(toolbarItems, animated: false)

        // 将toolbar添加到视图中
        view.addSubview(toolbar)

        // 设置toolbar的约束，使其位于屏幕底部
        toolbar.translatesAutoresizingMaskIntoConstraints = false
        let safeArea = view.safeAreaLayoutGuide
        NSLayoutConstraint.activate([
            toolbar.leadingAnchor.constraint(equalTo: safeArea.leadingAnchor),
            toolbar.trailingAnchor.constraint(equalTo: safeArea.trailingAnchor),
            toolbar.bottomAnchor.constraint(equalTo: safeArea.bottomAnchor)
        ])
    }

    @objc func exampleButtonTapped() {
        // 在这里处理按钮点击事件
    }
}