问如何允许WKWebView接受重定向url？

EN

import UIKit
import WebKit

class WebViewViewController: UIViewController, WKUIDelegate,       WKNavigationDelegate {

    var webView: WKWebView!

    override func viewDidLoad() {
        super.viewDidLoad()
        navigationController?.navigationBar.isHidden = false
        tabBarController?.tabBar.isHidden = true
        webView.navigationDelegate = self
        if let url = URL(string: "SomeUrl") {
            let request = URLRequest(url: url)
            webView.load(request)
        }
    }

    override func loadView() {
        let webConfiguration = WKWebViewConfiguration()
        webView = WKWebView(frame: .zero, configuration: webConfiguration)
        webView.uiDelegate = self
        view = webView
    }

    override func viewWillAppear(_ animated: Bool) {
        self.navigationController?.navigationBar.isHidden = false
    }

    override func viewWillDisappear(_ animated: Bool) {
        self.tabBarController?.tabBar.isHidden = false
    }

    func webViewDidFinishLoad(_ webView: UIWebView) {
        if let URL = webView.request?.url {
            OAuthHelper.oAuthManager.processOAuthStep1Response(url: URL)
        }
    }

    func webView(_ webView: WKWebView, didStartProvisionalNavigation navigation: WKNavigation!) {

    }

    func webView(_ webView: WKWebView, didReceiveServerRedirectForProvisionalNavigation navigation: WKNavigation!) {

    }

    func webView(_ webView: WKWebView, didReceive challenge: URLAuthenticationChallenge, completionHandler: @escaping (URLSession.AuthChallengeDisposition, URLCredential?) -> Void) {
        if challenge.previousFailureCount > 0 {
            completionHandler(Foundation.URLSession.AuthChallengeDisposition.cancelAuthenticationChallenge, nil)
        } else if let serverTrust = challenge.protectionSpace.serverTrust {
            completionHandler(Foundation.URLSession.AuthChallengeDisposition.useCredential, URLCredential(trust: serverTrust))
        } else {
            print("unknown state. error: \(challenge.error)")
            // do something w/ completionHandler here
        }
    }

    func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping (WKNavigationActionPolicy) -> Void) {
        if (navigationAction.navigationType == .linkActivated){
            decisionHandler(.cancel)
        } else {
            decisionHandler(.allow)
        }
    }
}