javascript alert and confirm popups not working with Webkit in IOS 9

Question

Javascript popups are not working for me with WebKit.

In Safari (on OSX) this document will create the expected alert and confirm popups. But with my WebKit instance running on IOS simulator or device the popups are not displayed and the confirm function returns false.

<!DOCTYPE html>
<html>
<body>

    <p id="check3"></p>

    <script>
        alert("alert 1");

        function check3() {
            return(confirm("Confirm?"));
        }
    </script>

    <button type="button"
        onclick="document.getElementById('check3').innerHTML = check3()">
        Check 3</button>

</body>
</html>

I am using Xcode 7.3, compiling for IOS 9.3. The info.plist has "AppTransportSecurity" to "Allow arbitrary HTML".

This is the code view controller code where I instantiate the web view:

import UIKit
import WebKit

class ViewController: UIViewController, WKNavigationDelegate {

  @IBOutlet weak var wv: UIView!

  var webView : WKWebView?

  override func viewDidAppear(animated: Bool) {
    super.viewDidAppear(true)

    let webViewCfg = WKWebViewConfiguration()
    webViewCfg.preferences.javaScriptEnabled = true;
    webViewCfg.preferences.javaScriptCanOpenWindowsAutomatically = true
    webView = WKWebView.init(frame:wv.bounds, configuration: webViewCfg)

    self.wv.addSubview(webView!)

    webView!.navigationDelegate = self

    let path = getBundlePath("js1.html")
    let targetFileURL = NSURL(fileURLWithPath: path!, isDirectory: false)
    webView!.loadFileURL(targetFileURL, allowingReadAccessToURL: targetFileURL)

  }
}

Thank you so much for that. I had spent a long time looking for an answer to that but for some reason never found the other answer. Much appreciated the swift version. — djruss70, Aug 13 '16 at 23:16
Please mark my answer as right if it works for you, I would appreciate, thanks :) — Marco Santarossa, Aug 13 '16 at 23:25
[IOS WKWebview not showing javascript alert() dialog](https://stackoverflow.com/q/26898941/6521116) — LF00, Jun 01 '17 at 02:43

score 2 · Accepted Answer · edited May 23 '17 at 10:28

From this answer

You must the webview delegate:

// MARK: WKUIDelegate methods
func webView(webView: WKWebView, runJavaScriptAlertPanelWithMessage message: String, initiatedByFrame frame: WKFrameInfo, completionHandler: (() -> Void)) {
    print("webView:\(webView) runJavaScriptAlertPanelWithMessage:\(message) initiatedByFrame:\(frame) completionHandler:\(completionHandler)")

    let alertController = UIAlertController(title: frame.request.URL?.host, message: message, preferredStyle: .Alert)
        alertController.addAction(UIAlertAction(title: "OK", style: .Default, handler: { action in
            completionHandler()
    }))
    self.presentViewController(alertController, animated: true, completion: nil)
}

javascript alert and confirm popups not working with Webkit in IOS 9

1 Answers1