如何强制UINavigationBar具有较小的高度？

class CustomNavigationBar: UINavigationBar {
    override func sizeThatFits(_ size: CGSize) -> CGSize {
        var newSize = super.sizeThatFits(size)
        newSize.height = 44 // 设置较小的高度
        return newSize
    }
}

class ViewController: UIViewController {
    override func viewDidLoad() {
        super.viewDidLoad()
        
        let customNavigationBar = CustomNavigationBar(frame: CGRect(x: 0, y: 0, width: view.frame.width, height: 44))
        customNavigationBar.backgroundColor = .white // 设置背景颜色
        customNavigationBar.tintColor = .black // 设置按钮颜色
        customNavigationBar.titleTextAttributes = [NSAttributedString.Key.foregroundColor: UIColor.black] // 设置标题颜色
        
        navigationController?.navigationBar.removeFromSuperview()
        navigationController?.navigationBar.isHidden = true
        view.addSubview(customNavigationBar)
    }
}