User-level events

Use NCUserHandler to receive user-level event callbacks — including subscription event changes, friend relationship changes, and multi-device sync notifications.

Register the handler via NCEngine with a unique identifier string:

Swift

swift

import NexconnChatSDK
// Register
NCEngine.addUserHandler(identifier: "MY_USER_HANDLER", handler: self)
// Remove
NCEngine.removeUserHandler(forIdentifier: "MY_USER_HANDLER")

Objective-C

Objective C

// Register
[NCEngine addUserHandlerWithIdentifier:@"MY_USER_HANDLER" handler:self];

// Remove
[NCEngine removeUserHandlerForIdentifier:@"MY_USER_HANDLER"];

Implement NCUserHandler

All methods are optional. Implement the callbacks you need.

Swift

swift

import NexconnChatSDK
final class MyViewController: NSObject, UserHandler {
    // Subscription event changed (e.g., online status update)
    func onSubscriptionChanged(_ event: SubscriptionChangedEvent) {
        for info in event.events {
            print("User event changed: \(info.userId)")
        }
    }

    // Subscription data sync completed
    func onSubscriptionSyncCompleted(_ event: SubscriptionSyncCompletedEvent) {
        print("Subscription synced for type: \(event.type.rawValue)")
    }

    // Subscription info changed on another device
    func onSubscriptionChangedOnOtherDevices(_ event: SubscriptionChangedOnOtherDevicesEvent) {
        print("Subscription changed on another device, count: \(event.events.count)")
    }

    // Friend added
    func onFriendAdd(_ event: FriendAddEvent) {
        print("Friend added: \(event.userId)")
    }

    // Friend deleted
    func onFriendDelete(_ event: FriendDeleteEvent) {
        print("Friends deleted: \(event.userIds)")
    }

    // All friends cleared (server-triggered only)
    func onFriendCleared(_ event: FriendClearedEvent) {
        print("All friends cleared at: \(event.operationTime)")
    }

    // Friend application status changed
    func onFriendApplicationStatusChanged(_ event: FriendApplicationStatusChangedEvent) {
        print("Friend application from \(event.userId) status: \(event.applicationStatus.rawValue)")
    }

    // Friend info changed on another device (multi-device sync)
    func onFriendInfoChangedSync(_ event: FriendInfoChangedSyncEvent) {
        print("Friend info synced for: \(event.userId)")
    }
}

Objective-C

Objective C

@interface MyViewController () <NCUserHandler>
@end

@implementation MyViewController

// Subscription event changed (e.g., online status update)
- (void)onSubscriptionChanged:(NCSubscriptionChangedEvent *)event {
    for (NCSubscriptionStatusInfo *info in event.events) {
        NSLog(@"User event changed: %@", info.userId);
    }
}

// Subscription data sync completed
- (void)onSubscriptionSyncCompleted:(NCSubscriptionSyncCompletedEvent *)event {
    NSLog(@"Subscription synced for type: %ld", (long)event.type);
}

// Subscription info changed on another device
- (void)onSubscriptionChangedOnOtherDevices:(NCSubscriptionChangedOnOtherDevicesEvent *)event {
    NSLog(@"Subscription changed on another device, count: %lu", (unsigned long)event.events.count);
}

// Friend added
- (void)onFriendAdd:(NCFriendAddEvent *)event {
    NSLog(@"Friend added: %@", event.userId);
}

// Friend deleted
- (void)onFriendDelete:(NCFriendDeleteEvent *)event {
    NSLog(@"Friends deleted: %@", event.userIds);
}

// All friends cleared (server-triggered only)
- (void)onFriendCleared:(NCFriendClearedEvent *)event {
    NSLog(@"All friends cleared at: %lld", (long long)event.operationTime);
}

// Friend application status changed
- (void)onFriendApplicationStatusChanged:(NCFriendApplicationStatusChangedEvent *)event {
    NSLog(@"Friend application from %@ status: %ld",
          event.userId, (long)event.applicationStatus);
}

// Friend info changed on another device (multi-device sync)
- (void)onFriendInfoChangedSync:(NCFriendInfoChangedSyncEvent *)event {
    NSLog(@"Friend info synced for: %@", event.userId);
}

@end

Callback reference

Callback	Event type	Trigger
onSubscriptionChanged:	NCSubscriptionChangedEvent	One or more subscription events changed (e.g., online status). Use event.events to iterate.
onSubscriptionSyncCompleted:	NCSubscriptionSyncCompletedEvent	Subscription data sync completed. Use event.type to identify the subscription type.
onSubscriptionChangedOnOtherDevices:	NCSubscriptionChangedOnOtherDevicesEvent	Subscription info changed on another device of the same user. Use event.events to iterate.
onFriendAdd:	NCFriendAddEvent	A friend was added. Use fields like event.userId, event.name, and event.operationTime.
onFriendDelete:	NCFriendDeleteEvent	One or more friends were removed. Use event.userIds for the affected list.
onFriendCleared:	NCFriendClearedEvent	All friends were cleared by a server-side operation. Use event.operationTime for the timestamp.
onFriendApplicationStatusChanged:	NCFriendApplicationStatusChangedEvent	A friend request status changed. Use fields like event.userId and event.applicationStatus.
onFriendInfoChangedSync:	NCFriendInfoChangedSyncEvent	Friend info changed on another device (multi-device sync). Use fields like event.userId and event.remark.

NCUserSettingsHandler

To receive user-level settings sync events, register an NCUserSettingsHandler separately:

Swift

swift

import NexconnChatSDK
// Register
NCEngine.addUserSettingsHandler(identifier: "MY_SETTINGS_HANDLER", handler: self)
// Remove
NCEngine.removeUserSettingsHandler(forIdentifier: "MY_SETTINGS_HANDLER")

Objective-C

Objective C

// Register
[NCEngine addUserSettingsHandlerWithIdentifier:@"MY_SETTINGS_HANDLER" handler:self];

// Remove
[NCEngine removeUserSettingsHandlerForIdentifier:@"MY_SETTINGS_HANDLER"];

Swift

swift

import NexconnChatSDK
final class MyViewController: NSObject, UserSettingsHandler {
    func onUserSettingsSyncCompleted(_ event: UserSettingsSyncCompletedEvent) {
        if event.error == nil {
            print("User settings synced successfully.")
        } else {
            print("User settings sync failed: \(event.error!.localizedDescription)")
        }
    }
}

Objective-C

Objective C

@interface MyViewController () <NCUserSettingsHandler>
@end

@implementation MyViewController

- (void)onUserSettingsSyncCompleted:(NCUserSettingsSyncCompletedEvent *)event {
    if (event.error == nil) {
        NSLog(@"User settings synced successfully.");
    } else {
        NSLog(@"User settings sync failed: %@", event.error);
    }
}

@end