iOS – ObjectiveC

📲 Handling FCM Token Registration in iOS

🔧 Objective-C Implementation in `AppDelegate.m`

The following code snippet captures the FCM registration token from Firebase and makes it available for use throughout the application or for SDK integrations like REL-ID:

@interface AppDelegate () <UNUserNotificationCenterDelegate>
@end

@implementation AppDelegate

@property (nonatomic, strong) NSString *deviceToken;

- (void)messaging:(FIRMessaging *)messaging
didReceiveRegistrationToken:(NSString *)fcmToken {
    
    NSLog(@"FCM registration token: %@", fcmToken);

    // Notify other parts of the app with the new token
    NSDictionary *dataDict = [NSDictionary dictionaryWithObject:fcmToken forKey:@"token"];
    [[NSNotificationCenter defaultCenter] postNotificationName:@"FCMToken" object:nil userInfo:dataDict];

    // TODO: If necessary, send the token to the application backend server

    // Save the token locally to provide it when requested (e.g., by the REL-ID SDK)
    self.deviceToken = fcmToken;
}

📌 Key Functionalities

Feature	Description
`didReceiveRegistrationToken:`	Called when Firebase generates or refreshes the FCM token.
`NSLog`	Logs the received token for debugging.
`NSNotificationCenter`	Broadcasts the new token across the app for any listening components.
`self.deviceToken = fcmToken`	Caches the token for later use by SDKs like REL-ID.

🧠 Notes

This method is automatically invoked:
- On first app launch after install.
- Whenever the FCM token is refreshed.
To expose this token to the REL-ID SDK, implement the getDeviceToken method as shown below:

- (NSString*)getDeviceToken {
    AppDelegate *delegate = (AppDelegate*)[UIApplication sharedApplication].delegate;
    return delegate.deviceToken;
}

🔁 Next Steps

Ensure FCM is properly configured with Firebase in your app.
Register for push notifications in didFinishLaunchingWithOptions.
Implement secure backend transmission of the token if required.

Updated 2 months ago