Monitor connection status

The Nexconn Chat SDK provides methods to retrieve and respond to IM connection status changes.

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Listen for connection status changes

Register a ConnectionStatusHandler to receive callbacks whenever the connection status changes. Register the handler after initializing the SDK and before connecting.

Swift

swift

import NexconnChatSDK

NCEngine.addConnectionStatusHandler(identifier: "MyConnectionHandler", handler: self)

Objective-C

Objective C

[NCEngine addConnectionStatusHandlerWithIdentifier:@"MyConnectionHandler" handler:self];

Implement the ConnectionStatusHandler protocol. In the current SDK, the callback receives a ConnectionStatusChangedEvent wrapper, and the actual state is available on event.status:

Swift

swift

import NexconnChatSDK

final class ConnectionMonitor: NSObject, ConnectionStatusHandler {
    func onConnectionStatusChanged(_ event: ConnectionStatusChangedEvent) {
        switch event.status {
        case .connected:
            print("Connected successfully.")
        case .networkUnavailable:
            print("Network unavailable; SDK will reconnect automatically.")
        case .tokenIncorrect:
            // Retrieve a new access token from your server and reconnect.
            break
        case .kickedOfflineByOtherClient:
            print("Kicked offline by another device.")
        default:
            print("Connection status changed: \(event.status.rawValue)")
        }
    }
}

Objective-C

Objective C

- (void)onConnectionStatusChanged:(NCConnectionStatusChangedEvent *)event {
    switch (event.status) {
        case NCConnectionStatusConnected:
            NSLog(@"Connected successfully.");
            break;
        case NCConnectionStatusNetworkUnavailable:
            NSLog(@"Network unavailable; SDK will reconnect automatically.");
            break;
        case NCConnectionStatusTokenIncorrect:
            // Retrieve a new access token from your server and reconnect
            break;
        case NCConnectionStatusKickedOfflineByOtherClient:
            NSLog(@"Kicked offline by another device.");
            break;
        default:
            NSLog(@"Connection status changed: %ld", (long)event.status);
            break;
    }
}

To remove the handler when it is no longer needed:

Swift

swift

import NexconnChatSDK

NCEngine.removeConnectionStatusHandler(forIdentifier: "MyConnectionHandler")

Objective-C

Objective C

[NCEngine removeConnectionStatusHandlerForIdentifier:@"MyConnectionHandler"];

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Get the current connection status

Call getConnectionStatus() at any time to actively retrieve the current IM connection status.

Swift

swift

import NexconnChatSDK

let status = NCEngine.getConnectionStatus()

Objective-C

Objective C

NCConnectionStatus status = [NCEngine getConnectionStatus];

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NCConnectionStatus enum

NCConnectionStatus defines all possible states during the IM connection lifecycle. The table below describes the key states your app needs to handle:

Value (ObjC)	rawValue	Description	Recommended Action
NCConnectionStatusUnknown	-1	Unknown status. The SDK usually reconnects automatically.	—
NCConnectionStatusConnected	0	Connected successfully.	—
NCConnectionStatusNetworkUnavailable	1	Current device network is unavailable. The SDK will reconnect automatically when the network recovers.	Display a network error indicator in the UI.
NCConnectionStatusKickedOfflineByOtherClient	6	The current user logged in on another device, and this device was kicked offline.	Navigate to the login screen and notify the user.
NCConnectionStatusConnecting	10	Connecting.	Show a loading indicator.
NCConnectionStatusUnconnected	11	Connection failed or not connected.	Notify the user based on your app's business logic.
NCConnectionStatusSignOut	12	Signed out.	—
NCConnectionStatusSuspend	13	Connection temporarily suspended; the SDK will reconnect at an appropriate time.	—
NCConnectionStatusTimeout	14	Auto-reconnect timed out (only occurs when a valid timeout is set). The SDK stops reconnecting after this.	Prompt the user to wait for network recovery and reconnect manually.
NCConnectionStatusTokenIncorrect	15	Access token is invalid or expired. This may occur if the client SDK and app server use different App Keys, or if the token has exceeded the expiry set in the console.	Request a new access token from the app server and reconnect with it.
NCConnectionStatusDisconnException	16	Disconnected from the server; the account has been banned.	Navigate to the login screen and notify the user of the account anomaly.
NCConnectionStatusProxyUnavailable	17	Proxy service is unavailable.	Check the proxy configuration and reconnect.
NCConnectionStatusUserAbandon	19	The user account has been deleted. No further reconnection attempts will be made.	Navigate to the login screen and notify the user that the account has been deactivated.

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Handle status in connection callbacks

When establishing a connection, use completionHandler to receive the connection result. Handle NCError.errorCode in the error callback:

Swift

swift

import NexconnChatSDK

let params = ConnectParams(token: "your_token")
params.timeout = 30

NCEngine.connect(
    params: params,
    databaseOpenedHandler: { isRecreated, error in
        guard error == nil else {
            print("Database open failed: \(error!.localizedDescription)")
            return
        }

        if isRecreated {
            print("Local data was recreated. Reload remote data if needed.")
        }
    },
    completionHandler: { userId, error in
        guard error == nil else {
            switch error!.errorCode {
            case 15:
                print("Token is invalid or expired. Request a new token and reconnect.")
            case 14:
                print("Connection timed out. Prompt the user to retry.")
            default:
                print("Connection failed, error code: \(error!.errorCode)")
            }
            return
        }

        print("Connected successfully, user ID: \(userId)")
    }
)

Objective-C

Objective C

NCConnectParams *params = [[NCConnectParams alloc] initWithToken:@"your_token"];
params.timeout = 30;

[NCEngine connectWithParams:params
      databaseOpenedHandler:^(BOOL isRecreated, NCError * _Nullable error) {
          if (error == nil) {
              if (isRecreated) {
                  NSLog(@"Local data was recreated. Reload remote data if needed.");
              }
          }
      }
         completionHandler:^(NSString *userId, NCError * _Nullable error) {
             if (error == nil) {
                 NSLog(@"Connected successfully, user ID: %@", userId);
             } else {
                 switch (error.errorCode) {
                     case 15:
                         // Retrieve a new access token and reconnect
                         break;
                     case 14:
                         // Connection timed out — notify the user
                         break;
                     default:
                         NSLog(@"Connection failed, error code: %ld", (long)error.errorCode);
                         break;
                 }
             }
         }];