override func viewDidLoad() {
    super.viewDidLoad()

    let navBarHeight: CGFloat = self.navigationController?.navigationBar.frame.height ?? 0.0


    title = "Webview"
    view.backgroundColor = .white

    let webView = UIWebView()
    webView.translatesAutoresizingMaskIntoConstraints = false

    view.addSubview(webView)

    webView.topAnchor.constraint(equalTo: self.view.topAnchor, constant: navBarHeight).isActive = true
    webView.leftAnchor.constraint(equalTo: self.view.leftAnchor).isActive = true
    webView.rightAnchor.constraint(equalTo: self.view.rightAnchor).isActive = true
    webView.bottomAnchor.constraint(equalTo: self.view.bottomAnchor).isActive = true

    let request = URLRequest(url: URL(string: "https://apple.com")!)
    webView.loadRequest(request)

}