使用 Xcode/Objective C 订阅 FCM 主题的问题

Question

我有一个无法解决的问题。我对 iOS/Xcode 的了解有限，请原谅我。

我正在尝试使用 xcode/Objective C 订阅 iOS 应用程序的 FCM 主题，但在加载应用程序时，它没有订阅该主题，在调试器中它甚至看起来不像是在尝试。

如果我移动[[FIRMessaging messaging] subscribeToTopic:@"/topics/channel"];行到正下方

[FIRMessaging messaging].delegate = self;
[application registerForRemoteNotifications];
[FIRApp configure];

(及以上return YES;(那么至少我收到此错误消息，表明它至少正在尝试。

2018-01-04 04:00:18.723760+0000 App[1049:1251125] [Firebase/Messaging][I-FCM002010] Cannot subscribe to topic: /topics/channel with token: (null)

因此，按照此处(以及许多其他地方(的建议，我试图将其移出didRegisterUserNotificationSettings但它似乎根本没有做任何事情，并且在调试器中也没有它的痕迹。

这是我的完整 AppDelegate.m 代码

//
//  AppDelegate.m
//
#import "AppDelegate.h"
#import <UserNotifications/UserNotifications.h>
#import <Firebase/Firebase.h>
#import <FirebaseMessaging/FirebaseMessaging.h>
#import <FirebaseInstanceID/FirebaseInstanceID.h>
#import <AFNetworking/AFNetworking.h>
@import Firebase;
@interface AppDelegate () <UNUserNotificationCenterDelegate, FIRMessagingDelegate>
@end
@implementation AppDelegate
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    [self setupNetworkReachability];
    [UNUserNotificationCenter currentNotificationCenter].delegate = self;
    UNAuthorizationOptions authOptions = UNAuthorizationOptionAlert | UNAuthorizationOptionSound | UNAuthorizationOptionBadge;
    [[UNUserNotificationCenter currentNotificationCenter] requestAuthorizationWithOptions:authOptions completionHandler:^(BOOL granted, NSError * _Nullable error)
    {
    }];
    [FIRMessaging messaging].delegate = self;
    [application registerForRemoteNotifications];
    [FIRApp configure];
    //[[FIRMessaging messaging] subscribeToTopic:@"/topics/channel"];
    return YES;
}
- (void)application:(UIApplication *)application didRegisterUserNotificationSettings:(UNNotificationSettings *)notificationSettings
{
    [[FIRMessaging messaging] subscribeToTopic:@"/topics/channel"];
    NSLog(@"Topic Registered");
}
- (void)applicationWillResignActive:(UIApplication *)application
{
}
- (void)applicationDidEnterBackground:(UIApplication *)application
{
}
- (void)applicationWillEnterForeground:(UIApplication *)application
{
}
- (void)applicationDidBecomeActive:(UIApplication *)application
{
}
- (void)applicationWillTerminate:(UIApplication *)application
{
}
#pragma mark - Public Methods
+ (AppDelegate *)sharedAppDelegate
{
    return (AppDelegate *)[[UIApplication sharedApplication] delegate];
}
- (void)setupNetworkReachability
{
    [[AFNetworkReachabilityManager sharedManager] setReachabilityStatusChangeBlock:^(AFNetworkReachabilityStatus status)
     {
         if (status == AFNetworkReachabilityStatusReachableViaWiFi || status == AFNetworkReachabilityStatusReachableViaWWAN)
             self.isNetworkAvailable = YES;
         else
             self.isNetworkAvailable = NO;
         NSLog(@"Reachability: %@", AFStringFromNetworkReachabilityStatus(status));
     }];
    [[AFNetworkReachabilityManager sharedManager] startMonitoring];
}
#pragma mark - FIRMessagingDelegate Methods
- (void)messaging:(nonnull FIRMessaging *)messaging didReceiveMessage:(nonnull FIRMessagingRemoteMessage *)remoteMessage
{
    NSLog(@"%@", remoteMessage.appData);
}
- (void)applicationReceivedRemoteMessage:(nonnull FIRMessagingRemoteMessage *)remoteMessage
{
    NSLog(@"%@", remoteMessage.appData);
}
- (void)userNotificationCenter:(UNUserNotificationCenter *)center willPresentNotification:(UNNotification *)notification withCompletionHandler:(void (^)(UNNotificationPresentationOptions options))completionHandler
{
    NSLog(@"%@", notification.request.content.userInfo);
    completionHandler(UNNotificationPresentationOptionAlert + UNNotificationPresentationOptionSound);
}
@end

将不胜感激任何帮助。谢谢。

只是

为了更新，该应用程序已经直接从FCM控制台接收消息，因此该部分工作正常，只是主题订阅失败。

Answer 1

1：你应该在[FIRMessaging messaging].delegate = self;之前调用[FIRApp configure];

2：当您发布AppDelegate.m文件的完整代码时。因此，它缺少以下更新/发送令牌到Firebase的方法。 您将在此UIApplication的委托方法中收到一个令牌，并且您必须为Firebase设置它(只需将此方法放在AppDelegate.m文件中即可(

- (void)application:(UIApplication *)application didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)deviceToken{
    NSString *strDevicetoken = [[NSString alloc]initWithFormat:@"%@",[[[deviceToken description] stringByTrimmingCharactersInSet:[NSCharacterSet characterSetWithCharactersInString:@"<>"]] stringByReplacingOccurrencesOfString:@" " withString:@""]];
    NSLog(@"Device Token = %@",strDevicetoken);
    [FIRMessaging messaging].APNSToken = deviceToken;
    //NSString *fcmToken = [FIRMessaging messaging].FCMToken;
    //NSLog(@"FCM registration token: %@", fcmToken);
}

现在，您已经在Firebase上

成功设置了APNS令牌，现在可以在Firebase上订阅所需的主题