`scene(_scene: UIScene, continue userActivity: NSUserActivity)` 在用户点击通用链接后启动应用程序时不会被调用

Question

在用户单击通用链接后启动应用程序时，不会调用方法 scene(_ scene: UIScene, continue userActivity: NSUserActivity)。

当用户点击通用链接后，已经启动的应用再次打开时，它工作正常。示例代码：

func scene(_ scene: UIScene, continue userActivity: NSUserActivity) {
    guard userActivity.activityType == NSUserActivityTypeBrowsingWeb,
        let incomingURL = userActivity.webpageURL,
        let components = NSURLComponents(url: incomingURL, resolvingAgainstBaseURL: true),
        let path = components.path else {
            return
    }
    let params = components.queryItems ?? [URLQueryItem]()

    print("path = \(path)")
    print("params = \(params)")
}

我尝试使用application(_ application: UIApplication, configurationForConnecting connectingSceneSession: UISceneSession, options: UIScene.ConnectionOptions) -> UISceneConfiguration，但是当用户点击链接时它永远不会被调用：

func application(_ application: UIApplication, configurationForConnecting connectingSceneSession: UISceneSession, options: UIScene.ConnectionOptions) -> UISceneConfiguration {
    if let scene = connectingSceneSession.scene, let userActivity = scene.userActivity {
        if userActivity.activityType == NSUserActivityTypeBrowsingWeb {
            if let incomingURL = userActivity.webpageURL,
                let components = NSURLComponents(url: incomingURL, resolvingAgainstBaseURL: true),
                let path = components.path {
                let params = components.queryItems ?? [URLQueryItem]()

                print("path = \(path)")
                print("params = \(params)")
            }
        }
    }
    return UISceneConfiguration(name: "Default Configuration", sessionRole: connectingSceneSession.role)
}

我尝试使用scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions)：

func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
    if let userActivity = scene.userActivity {
        self.scene(scene, continue: userActivity)
    }
}

我也尝试了以下方法：

func sceneDidBecomeActive(_ scene: UIScene) {
    if let userActivity = scene.userActivity {
        self.scene(scene, continue: userActivity)
    }
}

func sceneWillEnterForeground(_ scene: UIScene) {
    if let userActivity = scene.userActivity {
        self.scene(scene, continue: userActivity)
    }
}

但是scene.userActivity 总是为零，我无法得到userActivity.webpageURL。

我们如何识别链接被点击并且应用程序被启动（不仅仅是打开）？

Answer 1

Apple 回应确认 iOS 13 中存在该问题。

Answer 2

你差点就吃完了：

func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
    if let userActivity = scene.userActivity { // <-- not quite
        self.scene(scene, continue: userActivity)
    }
}

它不在场景中；它在connectionOptions 中。查看connectionOptions.userActivities。 （虽然如果发生的事情是用户点击了一个链接来启动我们，我希望在connectionOptions.urlContexts中找到该URL。）

Answer 3

这对我有用：

func scene(_ scene: UIScene, willConnectTo _: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
        for userActivity in connectionOptions.userActivities {
            if let url = userActivity.webpageURL { //ADD WHATEVER CONDITION YOU NEED
                //DO WHAT YOU NEED HERE
                break
            }
        }
    }

基本上问题是通用链接“隐藏”在connectionOptions中，因此您必须使用循环搜索它。

Answer 4

Matt 接受的答案适用于在应用尚未打开时启动通用链接。

如果您还想在应用打开时处理通用链接，则需要以下两个函数：

// SceneDelegate.swift
// This function is called when your app launches.
// Check to see if our app was launched with a universal link. 
func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
   // See if our app is being launched via universal link.
   for userActivity in connectionOptions.userActivities {
     if let universalLink = userActivity.webpageURL {
         // Do whatever you want with the universal link here.
         // NOTE: if you're navigating a web view, know that the web view will not be initialized here yet. 
         // To navigate a web view, store the URL in a variable and navigate to it once the web view is initialized.
     }
  }
}

// SceneDelegate.swift
// This function is called when your app is already running and a universal link to your app is clicked.
func scene(_ scene: UIScene, continue userActivity: NSUserActivity) {
    // Ensure we're trying to launch a link.
    guard userActivity.activityType == NSUserActivityTypeBrowsingWeb,
        let universalLink = userActivity.webpageURL else {
        return
    }

    // Handle the universal link here.
    // If you're navigating a web view, here's how I do it:
    //MyApp.webView.evaluateJavaScript("location.href = '\(universalLink)'")
}

我已验证这适用于我的应用。详情请见this Github thread。