Migrating UIWebView delegate to WKWebView delegate method

Question

I am working on migrating UIWebView to WKWebView. I have changed all the Delegate methods. I need WKWebView delegate methods equal to below UIWebView delegate method. The app is working fine. but login session is not retaining

UIWebView:

    extension WebViewController: UIWebViewDelegate {

    func webView(_ webView: UIWebView, shouldStartLoadWith request: URLRequest, navigationType: UIWebViewNavigationType) -> Bool {

    guard let url = request.url else {
       return true
    }

    guard !url.absoluteString.contains("data:application/pdf") else {
        navigationItem.rightBarButtonItem = UIBarButtonItem(barButtonSystemItem: UIBarButtonSystemItem.action,
                                                            target: self,
                                                            action: #selector(share(sender:)))
        return true
    }

    guard url.pathExtension != "pdf" else {
        let safariVC = SFSafariViewController(url: url)
        safariVC.modalPresentationStyle = .popover
        present(safariVC, animated: true, completion: nil)
        return false
    }

    guard url.isLogin() == false else {
        AppDelegate.navigationController.signOut(.sessionOnly)
        return false
    }

    guard let mobileSite = url.asMobileSite() else {
        return true
    }

    let mobileRedirect = URLRequest(url: mobileSite)
    webView.loadRequest(mobileRedirect)
    return false

}

func webViewDidStartLoad(_ webView: UIWebView) {
    numberOfDidStartLoads += 1
}

func webViewDidFinishLoad(_ webView: UIWebView) {
    numberOfDidStartLoads -= 1
}

func webView(_ webView: UIWebView, didFailLoadWithError error: Error) {
    numberOfDidStartLoads -= 1
}
}

And i tried below code and getting session expire.

extension WebViewController: UIWebViewDelegate {

    func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping (_: WKNavigationActionPolicy) -> Void) {

    guard let url = navigationAction.request.url else {
        decisionHandler(.allow)
        return
    }

    guard !url.absoluteString.contains("data:application/pdf") else {
        navigationItem.rightBarButtonItem = UIBarButtonItem(barButtonSystemItem: UIBarButtonSystemItem.action,
                                                            target: self,
                                                            action: #selector(share(sender:)))
        decisionHandler(.allow)
        return
    }

    guard url.pathExtension != "pdf" else {
        let safariVC = SFSafariViewController(url: url)
        safariVC.modalPresentationStyle = .popover
        present(safariVC, animated: true, completion: nil)
        decisionHandler(.cancel)
        return
    }

    guard url.isLogin() == false else {
        AppDelegate.navigationController.signOut(.sessionOnly)
        decisionHandler(.cancel)
        return
    }

    guard let mobileSite = url.asMobileSite() else {
        decisionHandler(.allow)
        return
    }

    let mobileRedirect = URLRequest(url: mobileSite)
    webView.load(mobileRedirect)
    decisionHandler(.cancel)
    return

    decisionHandler(.allow)

}

    func webViewDidStartLoad(_ webView: UIWebView) {
        numberOfDidStartLoads += 1
    }

    func webViewDidFinishLoad(_ webView: UIWebView) {
        numberOfDidStartLoads -= 1
    }

    func webView(_ webView: UIWebView, didFailLoadWithError error: Error) {
        numberOfDidStartLoads -= 1
    }
}

Please help me to resolve this issue. I have made some mistake in changing code from UIWebView to WKWebView.

Answer 1

You might required to implement the following in your code, which means instead of using UIWebViewDelegate protocol try to use WKNavigationDelegate protocol. I guess you are missing one of the most important function when you are handling with sessions .

   func webView(_ webView: WKWebView, didReceive challenge: URLAuthenticationChallenge, completionHandler: @escaping (URLSession.AuthChallengeDisposition, URLCredential?) -> Void) {
        print(#function)
        completionHandler(.performDefaultHandling,nil)
    }

There are different types of AuthChallengeDisposition , like

public enum AuthChallengeDisposition : Int {


    case useCredential

    case performDefaultHandling

    case cancelAuthenticationChallenge

    case rejectProtectionSpace
}

Complete WKNavigationDelegate protocols are

  extension ViewController: WKNavigationDelegate{
    func webViewWebContentProcessDidTerminate(_ webView: WKWebView) {
        print(#function)
    }

    func webView(_ webView: WKWebView, didCommit navigation: WKNavigation!) {
        print(#function)
    }

    func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) {
        print(#function)
    }

    func webView(_ webView: WKWebView, didStartProvisionalNavigation navigation: WKNavigation!) {
        print(#function)
    }

    func webView(_ webView: WKWebView, didFail navigation: WKNavigation!, withError error: Error) {
        print(#function)
    }

    func webView(_ webView: WKWebView, didReceiveServerRedirectForProvisionalNavigation navigation: WKNavigation!) {
        print(#function)
    }

    func webView(_ webView: WKWebView, didFailProvisionalNavigation navigation: WKNavigation!, withError error: Error) {
        print(#function)
    }

    func webView(_ webView: WKWebView, didReceive challenge: URLAuthenticationChallenge, completionHandler: @escaping (URLSession.AuthChallengeDisposition, URLCredential?) -> Void) {
        print(#function)
        completionHandler(.performDefaultHandling,nil)
    }

    func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping (WKNavigationActionPolicy) -> Void) {
        print(#function)
        decisionHandler(.allow)
    }

    func webView(_ webView: WKWebView, decidePolicyFor navigationResponse: WKNavigationResponse, decisionHandler: @escaping (WKNavigationResponsePolicy) -> Void) {
        print(#function)
        decisionHandler(.allow)
    }
}

Answer 2

I guess you can use webView(_:decidePolicyFor:decisionHandler:) and you block/cancel or allow requests. That should work in the same way.

Disclaimer: I haven't tested that yet, I'll do so as soon as I find some time.

Answer 3

analyzing your code, i have found a statement that is never reached cause of "return" called before.

The statement is:

decisionHandler(.allow)

You can find it as last line of code for the function:

func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping (_: WKNavigationActionPolicy) -> Void)

that you have up this method:

func webViewDidStartLoad(_ webView: UIWebView) {
    numberOfDidStartLoads += 1
}