ios - iOS 13 SceneDelegate 上的 WKWebView 警报崩溃

Question

*** Terminating app due to uncaught exception 'NSObjectNotAvailableException', reason: 'UIAlertView is deprecated and unavailable for UIScene based applications, please use UIAlertController!'

在 WKWebView 发出警报时，它会引发上述错误。

UIAlertView 是从网页中的 Javascript 调用的。我没有手动调用 UIAlertView。

import UIKit
import WebKit

class ViewController: UIViewController{

    @IBOutlet weak var webView: WKWebView!
    override func viewDidLoad() {
        super.viewDidLoad()

        let url = URL(string: "https://www.google.com/maps")!
        webView.load(URLRequest(url: url))
    }
}

当我点击“您的位置”时加载 map 后，应用程序崩溃。

Answer 1

我能够在模拟器上重现错误(版本 13.2.2)。我做了一个快速搜索，发现我们可以提供一个替代源来处理位置权限，并为 WKWebView 提供位置更新。下面是可以完成工作的代码。

ViewController.swift

import UIKit
import WebKit
class ViewController: UIViewController {

    var navigatorGeolocation = NavigatorGeolocation();
    var web: WKWebView!
    override func viewDidLoad() {
        super.viewDidLoad()

        let webViewConfiguration = WKWebViewConfiguration();
        navigatorGeolocation.setUserContentController(webViewConfiguration: webViewConfiguration);
        web = WKWebView(frame:.zero , configuration: webViewConfiguration)
        web.navigationDelegate = self;
        navigatorGeolocation.setWebView(webView: web);
        view.addSubview(web);
        web.translatesAutoresizingMaskIntoConstraints = false
        let constraints = [
            web.topAnchor.constraint(equalTo: view.topAnchor),
            web.leadingAnchor.constraint(equalTo: view.leadingAnchor),
            web.bottomAnchor.constraint(equalTo: view.bottomAnchor),
            web.trailingAnchor.constraint(equalTo: view.trailingAnchor)
        ]
        NSLayoutConstraint.activate(constraints)
        let url = URL(string: "https://www.google.com/maps")!
        web.load(URLRequest(url: url))
    }
}
extension ViewController: WKNavigationDelegate{
    func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) {
        webView.evaluateJavaScript(navigatorGeolocation.getJavaScripToEvaluate());
    }
}

NavigatorGeolocation.swift

import WebKit
import CoreLocation

class NavigatorGeolocation: NSObject, WKScriptMessageHandler, CLLocationManagerDelegate {

    var locationManager = CLLocationManager();
    var listenersCount = 0;
    var webView: WKWebView!;
    var controller: WKUserContentController?

    override init() {
        super.init();
        locationManager.delegate = self;
    }

    func setUserContentController(webViewConfiguration: WKWebViewConfiguration) {
        controller = WKUserContentController();
        controller?.add(self, name: "listenerAdded")
        controller?.add(self, name: "listenerRemoved")
        webViewConfiguration.userContentController = controller!
    }

    func setWebView(webView: WKWebView) {
        self.webView = webView;
    }

    func locationServicesIsEnabled() -> Bool {
        return (CLLocationManager.locationServicesEnabled()) ? true : false;
    }

    func authorizationStatusNeedRequest(status: CLAuthorizationStatus) -> Bool {
        return (status == .notDetermined) ? true : false;
    }

    func authorizationStatusIsGranted(status: CLAuthorizationStatus) -> Bool {
        return (status == .authorizedAlways || status == .authorizedWhenInUse) ? true : false;
    }

    func authorizationStatusIsDenied(status: CLAuthorizationStatus) -> Bool {
        return (status == .restricted || status == .denied) ? true : false;
    }

    func onLocationServicesIsDisabled() {
        webView.evaluateJavaScript("navigator.geolocation.helper.error(2, 'Location services disabled');");
    }

    func onAuthorizationStatusNeedRequest() {
        locationManager.requestWhenInUseAuthorization();
    }

    func onAuthorizationStatusIsGranted() {
        locationManager.startUpdatingLocation();
    }

    func onAuthorizationStatusIsDenied() {
        webView.evaluateJavaScript("navigator.geolocation.helper.error(1, 'App does not have location permission');");
    }

    func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
        if (message.name == "listenerAdded") {
            listenersCount += 1;

            if (!locationServicesIsEnabled()) {
                onLocationServicesIsDisabled();
            }
            else if (authorizationStatusIsDenied(status: CLLocationManager.authorizationStatus())) {
                onAuthorizationStatusIsDenied();
            }
            else if (authorizationStatusNeedRequest(status: CLLocationManager.authorizationStatus())) {
                onAuthorizationStatusNeedRequest();
            }
            else if (authorizationStatusIsGranted(status: CLLocationManager.authorizationStatus())) {
                onAuthorizationStatusIsGranted();
            }
        }
        else if (message.name == "listenerRemoved") {
            listenersCount -= 1;
            // no listener left in web view to wait for position
            if (listenersCount == 0) {
                locationManager.stopUpdatingLocation();
            }
        }
    }

    func locationManager(_ manager: CLLocationManager, didChangeAuthorization status: CLAuthorizationStatus) {
        // didChangeAuthorization is also called at app startup, so this condition checks listeners
        // count before doing anything otherwise app will start location service without reason
        if (listenersCount > 0) {
            if (authorizationStatusIsDenied(status: status)) {
                onAuthorizationStatusIsDenied();
            }
            else if (authorizationStatusIsGranted(status: status)) {
                onAuthorizationStatusIsGranted();
            }
        }
    }

    func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
        if let location = locations.last {
            webView.evaluateJavaScript("navigator.geolocation.helper.success('\(location.timestamp)', \(location.coordinate.latitude), \(location.coordinate.longitude), \(location.altitude), \(location.horizontalAccuracy), \(location.verticalAccuracy), \(location.course), \(location.speed));");
        }
    }

    func locationManager(_ manager: CLLocationManager, didFailWithError error: Error) {
        webView.evaluateJavaScript("navigator.geolocation.helper.error(2, 'Failed to get position (\(error.localizedDescription))');");
    }

    func getJavaScripToEvaluate() -> String {
        let javaScripToEvaluate = """
            // management for success and error listeners and its calling
            navigator.geolocation.helper = {
                listeners: {},
                noop: function() {},
                id: function() {
                    var min = 1, max = 1000;
                    return Math.floor(Math.random() * (max - min + 1)) + min;
                },
                clear: function(isError) {
                    for (var id in this.listeners) {
                        if (isError || this.listeners[id].onetime) {
                            navigator.geolocation.clearWatch(id);
                        }
                    }
                },
                success: function(timestamp, latitude, longitude, altitude, accuracy, altitudeAccuracy, heading, speed) {
                    var position = {
                        timestamp: new Date(timestamp).getTime() || new Date().getTime(), // safari can not parse date format returned by swift e.g. 2019-12-27 15:46:59 +0000 (fallback used because we trust that safari will learn it in future because chrome knows that format)
                        coords: {
                            latitude: latitude,
                            longitude: longitude,
                            altitude: altitude,
                            accuracy: accuracy,
                            altitudeAccuracy: altitudeAccuracy,
                            heading: (heading > 0) ? heading : null,
                            speed: (speed > 0) ? speed : null
                        }
                    };
                    for (var id in this.listeners) {
                        this.listeners[id].success(position);
                    }
                    this.clear(false);
                },
                error: function(code, message) {
                    var error = {
                        PERMISSION_DENIED: 1,
                        POSITION_UNAVAILABLE: 2,
                        TIMEOUT: 3,
                        code: code,
                        message: message
                    };
                    for (var id in this.listeners) {
                        this.listeners[id].error(error);
                    }
                    this.clear(true);
                }
            };

            // @override getCurrentPosition()
            navigator.geolocation.getCurrentPosition = function(success, error, options) {
                var id = this.helper.id();
                this.helper.listeners[id] = { onetime: true, success: success || this.noop, error: error || this.noop };
                window.webkit.messageHandlers.listenerAdded.postMessage("");
            };

            // @override watchPosition()
            navigator.geolocation.watchPosition = function(success, error, options) {
                var id = this.helper.id();
                this.helper.listeners[id] = { onetime: false, success: success || this.noop, error: error || this.noop };
                window.webkit.messageHandlers.listenerAdded.postMessage("");
                return id;
            };

            // @override clearWatch()
            navigator.geolocation.clearWatch = function(id) {
                var idExists = (this.helper.listeners[id]) ? true : false;
                if (idExists) {
                    this.helper.listeners[id] = null;
                    delete this.helper.listeners[id];
                    window.webkit.messageHandlers.listenerRemoved.postMessage("");
                }
            };
        """;

        return javaScripToEvaluate;
    }
}

NavigatorGeolocation 代码取自 Answer发表者 mikep

(提示:也请阅读评论)

输出(模拟器->调试->位置->苹果):