`willPresent notification` isn't called & local notifications aren't not showing up when the app is in the foreground in iOS 10

When I first run my app the simulator is able to display notifications whilst the app is in the foreground.

当我第一次运行我的应用程序时，模拟器能够在应用程序位于前台时显示通知。

When I relaunch the app didReceive notification: (i.e. notification method from iOS 9) is called instead of willPresent notification (i.e. notification method from iOS 10) and no notifications are displayed whilst the app is in the foreground. However, a notification is displayed if the app is in the background.

当我重新启动app didReceive通知时（即来自iOS 9的通知方法）被调用而不是willPresent通知（即来自iOS 10的通知方法），并且当应用程序在前台时不显示通知。但是，如果应用程序位于后台，则会显示通知。

Neither this question or this question provided a solution to this problem.

这个问题或这个问题都没有为这个问题提供解决方案。

I get authorisation for notifications using this code:

我使用此代码获得通知授权：

func application(_ application: UIApplication, willFinishLaunchingWithOptions launchOptions: [NSObject : AnyObject]? = [:]) -> Bool {
                if #available(iOS 10.0, *) {
                    let center = UNUserNotificationCenter.current() 
                    center.requestAuthorization(options: [.alert, .sound,  .sound]) { (granted, error) in              
                    UNUserNotificationCenter.current().delegate = self                   
                    }                      
                }
                return true
            }

And I've implemented the willPresent notification method:

我已经实现了willPresent通知方法：

@available(iOS 10.0, *)
            func userNotificationCenter(_ center: UNUserNotificationCenter,
                                        willPresent notification: UNNotification,
                                        withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void)                     completionHandler(UNNotificationPresentationOptions.alert)
            }

Here's how I create the notification:

以下是我创建通知的方法：

let content = UNMutableNotificationContent()
        content.title = title
        content.subtitle = subtitle
        content.body = message
        content.categoryIdentifier = identifier                      

        let trigger = UNTimeIntervalNotificationTrigger(
            timeInterval: 10.0,
            repeats: false)

        let request = UNNotificationRequest(
            identifier: "identifier",
            content: content,
            trigger: trigger
        )

        UNUserNotificationCenter.current().add(
            request, withCompletionHandler: nil)

Problem in a nutshell: How do I ensure the app is able to display a notification when the app is in the foreground after the first time that the app is run?

问题简而言之：在第一次运行应用程序后，如何确保应用程序在应用程序处于前台时能够显示通知？

Thanks in advance.

提前致谢。

1 个解决方案

#1

Try setting the delegate outside of the requestAuthorization completion block. It's probably happening later than you want.

尝试在requestAuthorization完成块之外设置委托。它可能比你想要的晚发生。

I added a sample project here: https://github.com/jerbeers/DemoLocalNotification

我在这里添加了一个示例项目：https：//github.com/jerbeers/DemoLocalNotification

If you build and run, tap the button, you'll see the local notification 3 seconds later. If you stop, build and run again, I see the local notification even while the app is running.

如果您构建并运行，请点击按钮，3秒后您将看到本地通知。如果您停止，构建并再次运行，即使应用程序正在运行，我也会看到本地通知。

#1