应用程序在 iOS 11 中处于后台时未收到推送通知

Posted 2023-02-24

【中文标题】应用程序在 iOS 11 中处于后台时未收到推送通知

【英文标题】：Push notification not received when App is in Background in iOS 11

【发布时间】：2018-04-11 07:05:50

【问题描述】：

我正在使用 UNUserNotificationCenter 在 ios 中发送推送通知。

当应用程序处于前台状态时，我能够收到通知。但是当App处于后台状态时，并没有收到通知。每当应用程序进入前台状态时，才会收到通知。

注册远程通知：

if(SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(@"10.0")) 
    [UNUserNotificationCenter currentNotificationCenter].delegate = self;
    [[UNUserNotificationCenter currentNotificationCenter] requestAuthorizationWithOptions:(UNAuthorizationOptionSound | UNAuthorizationOptionAlert | UNAuthorizationOptionBadge) completionHandler:^(BOOL granted, NSError * _Nullable error)
        if( !error )
            dispatch_async(dispatch_get_main_queue(), ^
                [[UIApplication sharedApplication] registerForRemoteNotifications];
            );
        
        else
            NSLog( @"Push registration FAILED" );
            NSLog( @"ERROR: %@ - %@", error.localizedFailureReason, error.localizedDescription );
            NSLog( @"SUGGESTIONS: %@ - %@", error.localizedRecoveryOptions, error.localizedRecoverySuggestion );
        
    ];

else 
    [[UIApplication sharedApplication] registerUserNotificationSettings:[UIUserNotificationSettings settingsForTypes:(UIUserNotificationTypeSound | UIUserNotificationTypeAlert | UIUserNotificationTypeBadge) categories:nil]];
    [[UIApplication sharedApplication] registerForRemoteNotifications];

当应用处于前台模式时，调用该方法：

- (void)userNotificationCenter:(UNUserNotificationCenter *)center
   willPresentNotification:(UNNotification *)notification
     withCompletionHandler:(void (^)(UNNotificationPresentationOptions))completionHandler

但此方法在后台模式下不起作用。 我提到了一些 *** 问题，但无法解决问题。 iOS 11 版有什么要添加的吗？

【问题讨论】：

你调用什么函数来发送通知？

@KakshilShah 现在检查我的问题。

Receiving Push Notifications while in background的可能重复

【参考方案1】：

如果是远程通知，则在应用委托中调用此方法：

    - (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo
    fetchCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler 
//Handle notification here!
    

【讨论】：

确保后台模式已启用远程通知

我正在使用 UNUserNotificationCenter 委托方法来接收远程通知：- (void)userNotificationCenter:(UNUserNotificationCenter *)center didReceiveNotificationResponse:(UNNotificationResponse *)response withCompletionHandler:(void(^)(void))completionHandler

@Kakshil Shah 只有当通知到达并且表明有数据要获取时才会触发该委托。 developer.apple.com/documentation/uikit/uiapplicationdelegate/…