如何根据底部的webview设置Viewcontroller的动态高度？

import UIKit
import WebKit

class ViewController: UIViewController, WKNavigationDelegate {

    var webView: WKWebView!
    var webViewHeightConstraint: NSLayoutConstraint!

    override func viewDidLoad() {
        super.viewDidLoad()

        // 创建webview
        webView = WKWebView()
        webView.translatesAutoresizingMaskIntoConstraints = false
        webView.navigationDelegate = self
        view.addSubview(webView)

        // 添加webview的约束
        webView.leadingAnchor.constraint(equalTo: view.leadingAnchor).isActive = true
        webView.trailingAnchor.constraint(equalTo: view.trailingAnchor).isActive = true
        webView.topAnchor.constraint(equalTo: view.topAnchor).isActive = true

        // 创建webview高度的约束
        webViewHeightConstraint = webView.heightAnchor.constraint(equalToConstant: 0)
        webViewHeightConstraint.isActive = true

        // 加载webview内容
        let url = URL(string: "https://www.example.com")
        let request = URLRequest(url: url!)
        webView.load(request)
    }

    func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) {
        // 获取webview内容高度
        let contentHeight = webView.scrollView.contentSize.height

        // 更新viewcontroller的高度
        webViewHeightConstraint.constant = contentHeight
        view.layoutIfNeeded()
    }
}