IOS 推送通知在前台 Swift 4.2

Question

我正在开发 IOS 应用程序，我正在使用 Parse SDK 处理推送通知。当我的背部处于后台时，我能够收到通知。现在我想接收通知，即使我的应用程序在前台。我已经为它搜索了许多代码，但它不适合我当前的 AppDelegate 类。

即使我的应用程序在前台，如何获取推送通知？

 @UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

    var window: UIWindow?


    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        // Thread.sleep(forTimeInterval: 3.0)
        // Override point for customization after application launch.

        let configuration = ParseClientConfiguration {
            $0.applicationId = "asdasdasd"
            $0.clientKey = "asdasdasdas"
            $0.server = "https://parseapi.back4app.com"
        }
        Parse.initialize(with: configuration)

        UNUserNotificationCenter.current().delegate = self as? UNUserNotificationCenterDelegate

        UNUserNotificationCenter.current().requestAuthorization(options: [.alert, .sound, .badge]) {
            (granted, error) in
            print("Permission granted: \(granted)")
            guard granted else { return }
            self.getNotificationSettings()
        }

        return true
    }

    func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void)
    {
        completionHandler([.alert, .badge, .sound])
    }

    func getNotificationSettings() {
        UNUserNotificationCenter.current().getNotificationSettings { (settings) in
            print("Notification settings: \(settings)")
            guard settings.authorizationStatus == .authorized else {
                return
            }
            DispatchQueue.main.async(execute: {
                UIApplication.shared.registerForRemoteNotifications()
            })
        }
    }

    func application(_ application: UIApplication,
                     didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data) {
        createInstallationOnParse(deviceTokenData: deviceToken)
    }


    func applicationWillResignActive(_ application: UIApplication) {

    }

    func applicationDidEnterBackground(_ application: UIApplication) {

    }

    func applicationWillEnterForeground(_ application: UIApplication) {

    }

    func applicationDidBecomeActive(_ application: UIApplication) {

    }

    func applicationWillTerminate(_ application: UIApplication) {

    }

    func application(_ application: UIApplication,
                     didFailToRegisterForRemoteNotificationsWithError error: Error) {
        print("Failed to register: \(error)")
    }
    }
}

我从同一个论坛找到了这个解决方案，但我无法将以下代码片段放入我当前的代码中:

func userNotificationCenter(_ center: UNUserNotificationCenter,
                                didReceive response: UNNotificationResponse,
                                withCompletionHandler completionHandler: @escaping () -> Void) {
        let userInfo = response.notification.request.content.userInfo


        // Print full message.
        print("tap on on forground app",userInfo)

        completionHandler()
    }

Answer 1

从 iOS 10 开始，Apple 允许用户在前台处理推送通知呈现。您可以在 willPresent 方法中处理它。并在 completionHandler 中处理推送通知，传递您想要的选项，即警报、角标(Badge)和声音。

确认您的 appDelegate 使用 UNUserNotificationCenterDelegate

将其放入您的didFinishLaunchingWithOptions 方法

UNUserNotificationCenter.current().delegate = self

之前

UNUserNotificationCenter.current().requestAuthorization(options: [.alert, .sound, .badge]) {
            (granted, error) in
            print("Permission granted: \(granted)")
            guard granted else { return }
            self.getNotificationSettings()
        }

并添加这个方法

 func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void)
    {
        completionHandler([.alert, .badge, .sound])
    }
    

iOS 14 更新.alert 已经过时，您现在应该使用 .banner，如下所示:

func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void)
       {
        completionHandler([.banner, .badge, .sound])
       }