All Real Time Listeners

Use CometChat real-time listeners for user presence, groups, messages, calls, AI assistant events, and ongoing calls.

CometChat provides 4 listeners viz.

1. User Listener
2. Group Listener
3. Message Listener
4. Call Listener
5. AI Assistant Listener
6. Ongoing Call Listener (Calls SDK)

User Listener

Receive online/offline presence events for users.

Method	Information
onUserOnline(user: CometChat.User)	This method is triggered when a user comes online and is available to chat. The details of the user can be obtained from the user object received as the method parameter.
onUserOffline(user: CometChat.User)	This method is triggered when a user goes offline. The details of the user can be obtained from the User object received as the parameter.

To add the UserListener:

TypeScript

const listenerID: string = "UNIQUE_LISTENER_ID";
CometChat.addUserListener(
  listenerID,
  new CometChat.UserListener({
    onUserOnline: (onlineUser: CometChat.User) => {
      /* when someuser/friend comes online, user will be received here */
      console.log("On User Online:", { onlineUser });
    },
    onUserOffline: (offlineUser: CometChat.User) => {
      /* when someuser/friend went offline, user will be received here */
      console.log("On User Offline:", { offlineUser });
    },
  })
);

JavaScript

const listenerID = "UNIQUE_LISTENER_ID";
CometChat.addUserListener(
  listenerID,
  new CometChat.UserListener({
    onUserOnline: (onlineUser) => {
      console.log("On User Online:", { onlineUser });
    },
    onUserOffline: (offlineUser) => {
      console.log("On User Offline:", { offlineUser });
    },
  })
);

Remove the listener when no longer needed:

TypeScript

let listenerID: string = "UNIQUE_LISTENER_ID";
CometChat.removeUserListener(listenerID);

JavaScript

let listenerID = "UNIQUE_LISTENER_ID";
CometChat.removeUserListener(listenerID);

Group Listener

Receive events when group members join, leave, are kicked/banned, or have their scope changed.

Method	Information
onGroupMemberJoined(action: CometChat.Action, joinedUser: CometChat.User, joinedGroup: CometChat.Group)	This method is triggered when a user joins any group. All the members present in the group will receive this event.
onGroupMemberLeft(action: CometChat.Action, leftUser: CometChat.User, leftGroup: CometChat.Group)	This method is triggered when a user who was a member of any group leaves the group. All the members of the group receive this event.
onGroupMemberKicked(action: CometChat.Action, kickedUser: CometChat.User, kickedBy: CometChat.User, kickedFrom: CometChat.Group)	This method is triggered when a user is kicked from a group. All the members including the user receive this event
onGroupMemberBanned(action: CometChat.Action, bannedUser: CometChat.User, bannedBy: CometChat.User, bannedFrom: CometChat.Group)	This method is triggered when a user is banned from a group. All the members including the user receive this event
onGroupMemberUnbanned(action: CometChat.Action, unbannedUser: CometChat.User, unbannedBy: CometChat.User, unbannedFrom: CometChat.Group)	This method is triggered when a user is banned from a group. All the members of the group receive this event.
onGroupMemberScopeChanged(action: CometChat.Action, changedUser: CometChat.User, newScope: string, oldScope: string, changedGroup: CometChat.Group)	This method is triggered when the scope of any Group Member has been changed. All the members that are a part of that group receive this event
onMemberAddedToGroup(action: CometChat.Action, userAdded: CometChat.User, addedBy: CometChat.User, addedTo: CometChat.Group)	This method is triggered when a user is added to any group. All the members including the user himself receive this event.

To add the GroupListener:

TypeScript

CometChat.addGroupListener(
  "UNIQUE_LISTENER_ID",
  new CometChat.GroupListener({
    onGroupMemberJoined: (
      message: CometChat.Action,
      joinedUser: CometChat.User,
      joinedGroup: CometChat.Group
    ) => {
      console.log("onGroupMemberJoined", { message, joinedUser, joinedGroup });
    },
    onGroupMemberLeft: (
      message: CometChat.Action,
      leftUser: CometChat.User,
      leftGroup: CometChat.Group
    ) => {
      console.log("onGroupMemberLeft", { message, leftUser, leftGroup });
    },
    onGroupMemberKicked: (
      message: CometChat.Action,
      kickedUser: CometChat.User,
      kickedBy: CometChat.User,
      kickedFrom: CometChat.Group
    ) => {
      console.log("onGroupMemberKicked", {
        message,
        kickedUser,
        kickedBy,
        kickedFrom,
      });
    },
    onGroupMemberBanned: (
      message: CometChat.Action,
      bannedUser: CometChat.User,
      bannedBy: CometChat.User,
      bannedFrom: CometChat.Group
    ) => {
      console.log("onGroupMemberBanned", {
        message,
        bannedUser,
        bannedBy,
        bannedFrom,
      });
    },
    onGroupMemberUnbanned: (
      message: CometChat.Action,
      unbannedUser: CometChat.User,
      unbannedBy: CometChat.User,
      unbannedFrom: CometChat.Group
    ) => {
      console.log("onGroupMemberUnbanned", {
        message,
        unbannedUser,
        unbannedBy,
        unbannedFrom,
      });
    },
    onGroupMemberScopeChanged: (
      message: CometChat.Action,
      changedUser: CometChat.User,
      newScope: string,
      oldScope: string,
      changedGroup: CometChat.Group
    ) => {
      console.log("onGroupMemberScopeChanged", {
        message,
        changedUser,
        newScope,
        oldScope,
        changedGroup,
      });
    },
    onMemberAddedToGroup: (
      message: CometChat.Action,
      userAdded: CometChat.User,
      addedby: CometChat.User,
      addedTo: CometChat.Group
    ) => {
      console.log("onMemberAddedToGroup", {
        message,
        userAdded,
        addedby,
        addedTo,
      });
    },
  })
);

JavaScript

CometChat.addGroupListener(
  "UNIQUE_LISTENER_ID",
  new CometChat.GroupListener({
    onGroupMemberJoined: (message, joinedUser, joinedGroup) => {
      console.log("onGroupMemberJoined", { message, joinedUser, joinedGroup });
    },
    onGroupMemberLeft: (message, leftUser, leftGroup) => {
      console.log("onGroupMemberLeft", { message, leftUser, leftGroup });
    },
    onGroupMemberKicked: (message, kickedUser, kickedBy, kickedFrom) => {
      console.log("onGroupMemberKicked", {
        message,
        kickedUser,
        kickedBy,
        kickedFrom,
      });
    },
    onGroupMemberBanned: (message, bannedUser, bannedBy, bannedFrom) => {
      console.log("onGroupMemberBanned", {
        message,
        bannedUser,
        bannedBy,
        bannedFrom,
      });
    },
    onGroupMemberUnbanned: (
      message,
      unbannedUser,
      unbannedBy,
      unbannedFrom
    ) => {
      console.log("onGroupMemberUnbanned", {
        message,
        unbannedUser,
        unbannedBy,
        unbannedFrom,
      });
    },
    onGroupMemberScopeChanged: (
      message,
      changedUser,
      newScope,
      oldScope,
      changedGroup
    ) => {
      console.log("onGroupMemberScopeChanged", {
        message,
        changedUser,
        newScope,
        oldScope,
        changedGroup,
      });
    },
    onMemberAddedToGroup: (message, userAdded, addedby, addedTo) => {
      console.log("onMemberAddedToGroup", {
        message,
        userAdded,
        addedby,
        addedTo,
      });
    },
  })
);

Remove the listener when no longer needed:

TypeScript

let listenerID: string = "UNIQUE_LISTENER_ID";
CometChat.removeGroupListener(listenerID);

JavaScript

let listenerID = "UNIQUE_LISTENER_ID";
CometChat.removeGroupListener(listenerID);

Message Listener

Receive events for incoming messages, typing indicators, read/delivery receipts, message edits/deletes, reactions, and moderation results.

Method	Information
onTextMessageReceived(message: CometChat.TextMessage)	This event is triggered when a Text Message is received.
onMediaMessageReceived(message: CometChat.MediaMessage)	This event is triggered when a Media Message is received.
onCustomMessageReceived(message: CometChat.CustomMessage)	This event is triggered when a Custom Message is received.
onTypingStarted(typingIndicator: CometChat.TypingIndicator)	This event is triggered when a user starts typing in a user/group conversation
onTypingEnded(typingIndicator: CometChat.TypingIndicator)	This event is triggered when a user stops typing in a user/group conversation.
onMessagesDelivered(messageReceipt: CometChat.MessageReceipt)	This event is triggered when a set of messages are marked as delivered for any particular conversation.
onMessagesRead(messageReceipt: CometChat.MessageReceipt)	This event is triggered when a set of messages are marked as read for any particular conversation.
onMessageEdited(message: CometChat.BaseMessage)	This method is triggered when a particular message has been edited in a user/group conversation.
onMessageDeleted(message: CometChat.BaseMessage)	This event is triggered when a particular message is deleted in a user/group conversation.
onTransientMessageReceived(receipt: CometChat.TransientMessage)	This event is triggered when a Transient Message is received.
onMessageReactionAdded(receipt: CometChat.ReactionEvent)	This event is triggered when a reaction is added to a message in a user/group conversation.
onMessageReactionRemoved(receipt: CometChat.ReactionEvent)	This event is triggered when a reaction is remove from a message in a user/group conversation.
onMessageModerated(message: CometChat.BaseMessage)	This event is triggered when a message sent by the logged-in user is successfully processed by moderation and receives either an approved or disapproved status.
onMessagesDeliveredToAll(receipt: CometChat.MessageReceipt)	This event is triggered when a group message is delivered to all members. Group conversations only.
onMessagesReadByAll(receipt: CometChat.MessageReceipt)	This event is triggered when a group message is read by all members. Group conversations only.
onAIAssistantMessageReceived(message: CometChat.AIAssistantMessage)	This event is triggered when a persisted AI assistant reply is received after an agent run completes.
onAIToolResultReceived(message: CometChat.AIToolResultMessage)	This event is triggered when a persisted AI tool result message is received after an agent run completes.
onAIToolArgumentsReceived(message: CometChat.AIToolArgumentMessage)	This event is triggered when a persisted AI tool argument message is received after an agent run completes.
onCardMessageReceived(message: CometChat.CardMessage)	This event is triggered when a standalone card message is received.

To add the MessageListener, you need to use the addMessageListener() method provided by the CometChat class.

TypeScript

CometChat.addMessageListener(
  "UNIQUE_LISTENER_ID",
  new CometChat.MessageListener({
    onTextMessageReceived: (textMessage: CometChat.TextMessage) => {
      console.log("Text message received successfully", textMessage);
    },
    onMediaMessageReceived: (mediaMessage: CometChat.MediaMessage) => {
      console.log("Media message received successfully", mediaMessage);
    },
    onCustomMessageReceived: (customMessage: CometChat.CustomMessage) => {
      console.log("Custom message received successfully", customMessage);
    },
    onMessagesDelivered: (messageReceipt: CometChat.MessageReceipt) => {
      console.log("Message Delivered", messageReceipt);
    },
    onMessagesRead: (messageReceipt: CometChat.MessageReceipt) => {
      console.log("Message Read", messageReceipt);
    },
    onTypingStarted: (typingIndicator: CometChat.TypingIndicator) => {
      console.log("Typing Started", typingIndicator);
    },
    onTypingEnded: (typingIndicator: CometChat.TypingIndicator) => {
      console.log("Typing Ended", typingIndicator);
    },
    onMessageDeleted: (message: CometChat.BaseMessage) => {
      console.log("Message Delted", message);
    },
    onMessageEdited: (message: CometChat.BaseMessage) => {
      console.log("Message Edited", message);
    },
    onTransientMessageReceived: (message: CometChat.TransientMessage) => {
      console.log("Transient Message received", message);
    },
    onMessageReactionAdded: (reaction: CometChat.ReactionEvent) => {
      console.log("Message Reaction added", reaction);
    },
    onMessageReactionRemoved: (reaction: CometChat.ReactionEvent) => {
      console.log("Message Reaction removed", reaction);
    },
    onMessageModerated: (message: CometChat.BaseMessage) => {
      console.log("Message Moderated", message);
    },
    onMessagesDeliveredToAll: (messageReceipt: CometChat.MessageReceipt) => {
      console.log("Message Delivered to All", messageReceipt);
    },
    onMessagesReadByAll: (messageReceipt: CometChat.MessageReceipt) => {
      console.log("Message Read by All", messageReceipt);
    },
    onAIAssistantMessageReceived: (message: CometChat.AIAssistantMessage) => {
      console.log("AI Assistant message received", message);
    },
    onAIToolResultReceived: (message: CometChat.AIToolResultMessage) => {
      console.log("AI Tool result received", message);
    },
    onAIToolArgumentsReceived: (message: CometChat.AIToolArgumentMessage) => {
      console.log("AI Tool arguments received", message);
    },
    onCardMessageReceived: (message: CometChat.CardMessage) => {
      console.log("Card message received", message);
    },
  })
);

JavaScript

CometChat.addMessageListener(
  "UNIQUE_LISTENER_ID",
  new CometChat.MessageListener({
    onTextMessageReceived: (textMessage) => {
      console.log("Text message received successfully", textMessage);
    },
    onMediaMessageReceived: (mediaMessage) => {
      console.log("Media message received successfully", mediaMessage);
    },
    onCustomMessageReceived: (customMessage) => {
      console.log("Custom message received successfully", customMessage);
    },
    onMessagesDelivered: (messageReceipt) => {
      console.log("Message Delivered", messageReceipt);
    },
    onMessagesRead: (messageReceipt) => {
      console.log("Message Read", messageReceipt);
    },
    onTypingStarted: (typingIndicator) => {
      console.log("Typing Started", typingIndicator);
    },
    onTypingEnded: (typingIndicator) => {
      console.log("Typing Ended", typingIndicator);
    },
    onMessageDeleted: (message) => {
      console.log("Message Deleted", message);
    },
    onMessageEdited: (message) => {
      console.log("Message Edited", message);
    },
    onTransientMessageReceived: (message) => {
      console.log("Transient Message received", message);
    },
    onMessageReactionAdded: (reaction) => {
      console.log("Message Reaction added", reaction);
    },
    onMessageReactionRemoved: (reaction) => {
      console.log("Message Reaction removed", reaction);
    },
    onMessageModerated: (message) => {
      console.log("Message Moderated", message);
    },
    onMessagesDeliveredToAll: (messageReceipt) => {
      console.log("Message Delivered to All", messageReceipt);
    },
    onMessagesReadByAll: (messageReceipt) => {
      console.log("Message Read by All", messageReceipt);
    },
    onAIAssistantMessageReceived: (message) => {
      console.log("AI Assistant message received", message);
    },
    onAIToolResultReceived: (message) => {
      console.log("AI Tool result received", message);
    },
    onAIToolArgumentsReceived: (message) => {
      console.log("AI Tool arguments received", message);
    },
    onCardMessageReceived: (message) => {
      console.log("Card message received", message);
    },
  })
);

Remove the listener when no longer needed:

TypeScript

let listenerID: string = "UNIQUE_LISTENER_ID";
CometChat.removeMessageListener(listenerID);

JavaScript

let listenerID = "UNIQUE_LISTENER_ID";
CometChat.removeMessageListener(listenerID);

Call Listener

Receive events for incoming and outgoing call state changes.

Method	Information
onIncomingCallReceived(call: CometChat.Call)	This event is triggered when the logged-in user receives an incoming call. The details of the call can be obtained from the Call object received as the method parameter.
onOutgoingCallAccepted(call: CometChat.Call)	This event is triggered when the call initiated by the logged-in user is accepted by the recipient. The details of the call can be obtained from the Call object received as the method parameter.
onOutgoingCallRejected(call: CometChat.Call)	This event is triggered when the call initiated by the logged-in user is rejected by the recipient. The details of the call can be obtained from the Call object received as the method parameter
onIncomingCallCancelled(call: CometChat.Call)	This event is triggered when an incoming call is canceled by the initiator of the call. The details of the call can be obtained from the Call object received as the method parameter
onCallEndedMessageReceived(call: CometChat.Call)	This event is triggered when a call ends. The call object contains the final status and duration.

To add the CallListener:

TypeScript

CometChat.addCallListener(
  "UNIQUE_LISTENER_ID",
  new CometChat.CallListener({
    onIncomingCallReceived: (call: CometChat.Call) => {
      console.log("Incoming call:", call);
    },
    onOutgoingCallAccepted: (call: CometChat.Call) => {
      console.log("Outgoing call accepted:", call);
    },
    onOutgoingCallRejected: (call: CometChat.Call) => {
      console.log("Outgoing call rejected:", call);
    },
    onIncomingCallCancelled: (call: CometChat.Call) => {
      console.log("Incoming call canceled:", call);
    },
    onCallEndedMessageReceived: (call: CometChat.Call) => {
      console.log("Call ended message:", call);
    },
  })
);

JavaScript

CometChat.addCallListener(
  "UNIQUE_LISTENER_ID",
  new CometChat.CallListener({
    onIncomingCallReceived(call) {
      console.log("Incoming call:", call);
    },
    onOutgoingCallAccepted(call) {
      console.log("Outgoing call accepted:", call);
    },
    onOutgoingCallRejected(call) {
      console.log("Outgoing call rejected:", call);
    },
    onIncomingCallCancelled(call) {
      console.log("Incoming call canceled:", call);
    },
    onCallEndedMessageReceived(call) {
      console.log("Call ended message:", call);
    },
  })
);

Remove the listener when no longer needed:

TypeScript

let listenerID: string = "UNIQUE_LISTENER_ID";
CometChat.removeCallListener(listenerID);

JavaScript

let listenerID = "UNIQUE_LISTENER_ID";
CometChat.removeCallListener(listenerID);

---

AI Assistant Listener

The AIAssistantListener provides real-time streaming events from AI Agent runs. These events are received as the agent processes a user’s message, before the final persisted messages arrive via the MessageListener.

Method	Information
onAIAssistantEventReceived(event: CometChat.AIAssistantBaseEvent)	This event is triggered for each streaming event during an AI Agent run (run start, tool calls, text message streaming, card streaming, run finished). See AIAssistantBaseEvent for the event structure.

Card streaming (card_start, card, card_end) is delivered through this same callback as AIAssistantCardStartedEvent, AIAssistantCardReceivedEvent, and AIAssistantCardEndedEvent. See the Card Messages guide.

TypeScript

const listenerID: string = "UNIQUE_LISTENER_ID";
CometChat.addAIAssistantListener(
  listenerID,
  new CometChat.AIAssistantListener({
    onAIAssistantEventReceived: (event: CometChat.AIAssistantBaseEvent) => {
      console.log("AI Assistant event:", event.getType(), event);
    },
  })
);

JavaScript

const listenerID = "UNIQUE_LISTENER_ID";
CometChat.addAIAssistantListener(
  listenerID,
  new CometChat.AIAssistantListener({
    onAIAssistantEventReceived: (event) => {
      console.log("AI Assistant event:", event.getType(), event);
    },
  })
);

To remove the listener:

TypeScript

typescript CometChat.removeAIAssistantListener("UNIQUE_LISTENER_ID");

JavaScript

javascript CometChat.removeAIAssistantListener("UNIQUE_LISTENER_ID");

Ongoing Call Listener (Calls SDK)

The OngoingCallListener provides real-time callbacks for active call session events. It is part of the CometChat Calls SDK (not the Chat SDK) and is used with CallSettingsBuilder.setCallListener() or CometChatCalls.addCallEventListener().

All three calling flows — Call Session, Standalone Calling, and Ringing — use the same OngoingCallListener.

Callbacks

Callback	Parameter	Description
onUserJoined(user)	user object	A remote participant joined the call
onUserLeft(user)	user object	A remote participant left the call
onUserListUpdated(userList)	Array of user objects	The participant list changed (join or leave)
onCallEnded()	—	The call session terminated (1:1 calls only, fires for both participants)
onCallEndButtonPressed()	—	The local user clicked the end call button
onSessionTimeout()	—	The call was auto-terminated due to inactivity. v4.1.0+
onScreenShareStarted()	—	The local user started sharing their screen
onScreenShareStopped()	—	The local user stopped sharing their screen
onUserMuted(event)	event object	A participant’s mute state changed
onCallSwitchedToVideo(event)	event object	An audio call was upgraded to video
onMediaDeviceListUpdated(deviceList)	deviceList object	Available audio/video devices changed
onRecordingStarted(event)	event object	A user started recording the call
onRecordingStopped()	—	Recording was stopped
onError(error)	CometChatCallsException	An error occurred during the call session

Callback Parameter Shapes

user object (received by onUserJoined, onUserLeft):

Property	Type	Description
name	string	Display name of the user
avatar	string	URL of the user’s avatar
uid	string	UID of the user

onUserListUpdated(userList) — receives an array of user objects with the same shape as above.

onUserMuted(event):

Property	Type	Description
event.muted.name	string	Name of the muted user
event.muted.uid	string	UID of the muted user
event.muted.isAudioMuted	boolean	Whether audio is muted
event.muted.isVideoMuted	boolean	Whether video is muted
event.mutedBy.name	string	Name of the user who muted
event.mutedBy.uid	string	UID of the user who muted

onCallSwitchedToVideo(event):

Property	Type	Description
event.sessionId	string	Session ID of the call
event.initiator.name	string	Name of the user who initiated the switch
event.initiator.uid	string	UID of the initiator
event.responder.name	string	Name of the responder
event.responder.uid	string	UID of the responder

onMediaDeviceListUpdated(deviceList):

Property	Type	Description
deviceList.videoInputDevices	MediaDeviceInfo[]	Available cameras
deviceList.audioInputDevices	MediaDeviceInfo[]	Available microphones
deviceList.audioOutputDevices	MediaDeviceInfo[]	Available speakers/headphones

onRecordingStarted(event):

Property	Type	Description
event.user.name	string	Name of the user who started recording
event.user.uid	string	UID of the user who started recording

onRecordingStopped(), onCallEnded(), onSessionTimeout(), onCallEndButtonPressed(), onScreenShareStarted(), onScreenShareStopped() — receive no arguments.

TypeScript

const listenerId: string = "UNIQUE_LISTENER_ID";

CometChatCalls.addCallEventListener(listenerId, {
onUserJoined: (user: any) => {
console.log("User joined:", user);
},
onUserLeft: (user: any) => {
console.log("User left:", user);
},
onCallEnded: () => {
console.log("Call ended");
},
onCallEndButtonPressed: () => {
console.log("End call button pressed");
},
onError: (error: any) => {
console.log("Call error:", error);
},
});

// Remove listener when done
CometChatCalls.removeCallEventListener(listenerId);

JavaScript

const listenerId = "UNIQUE_LISTENER_ID";

CometChatCalls.addCallEventListener(listenerId, {
  onUserJoined: (user) => {
    console.log("User joined:", user);
  },
  onUserLeft: (user) => {
    console.log("User left:", user);
  },
  onCallEnded: () => {
    console.log("Call ended");
  },
  onCallEndButtonPressed: () => {
    console.log("End call button pressed");
  },
  onError: (error) => {
    console.log("Call error:", error);
  },
});

// Remove listener when done
CometChatCalls.removeCallEventListener(listenerId);

---

Login Listener

Receive events when the user’s authentication state changes — login success/failure and logout success/failure.

Method	Description
loginSuccess(user)	User logged in successfully. Provides the User object.
loginFailure(error)	Login failed. Provides a CometChatException.
logoutSuccess()	User logged out successfully.
logoutFailure(error)	Logout failed. Provides a CometChatException.

TypeScript

const listenerID: string = "UNIQUE_LISTENER_ID";
CometChat.addLoginListener(
  listenerID,
  new CometChat.LoginListener({
    loginSuccess: (user: CometChat.User) => {
      console.log("LoginListener :: loginSuccess", user);
    },
    loginFailure: (error: CometChat.CometChatException) => {
      console.log("LoginListener :: loginFailure", error);
    },
    logoutSuccess: () => {
      console.log("LoginListener :: logoutSuccess");
    },
    logoutFailure: (error: CometChat.CometChatException) => {
      console.log("LoginListener :: logoutFailure", error);
    }
  })
);

JavaScript

const listenerID = "UNIQUE_LISTENER_ID";
CometChat.addLoginListener(
  listenerID,
  new CometChat.LoginListener({
    loginSuccess: (user) => {
      console.log("LoginListener :: loginSuccess", user);
    },
    loginFailure: (error) => {
      console.log("LoginListener :: loginFailure", error);
    },
    logoutSuccess: () => {
      console.log("LoginListener :: logoutSuccess");
    },
    logoutFailure: (error) => {
      console.log("LoginListener :: logoutFailure", error);
    }
  })
);

Remove the listener when no longer needed:

CometChat.removeLoginListener("UNIQUE_LISTENER_ID");

Connection Listener

Receive events when the WebSocket connection state changes.

Method	Description
onConnected()	SDK has an active connection to CometChat servers.
inConnecting()	SDK is attempting to establish or re-establish a connection.
onDisconnected()	SDK is disconnected due to network issues or other errors.
onFeatureThrottled()	A feature has been throttled due to rate limiting.

TypeScript

const listenerID: string = "UNIQUE_LISTENER_ID";
CometChat.addConnectionListener(
  listenerID,
  new CometChat.ConnectionListener({
    onConnected: () => {
      console.log("ConnectionListener :: connected");
    },
    inConnecting: () => {
      console.log("ConnectionListener :: connecting");
    },
    onDisconnected: () => {
      console.log("ConnectionListener :: disconnected");
    },
    onFeatureThrottled: () => {
      console.log("ConnectionListener :: feature throttled");
    }
  })
);

JavaScript

const listenerID = "UNIQUE_LISTENER_ID";
CometChat.addConnectionListener(
  listenerID,
  new CometChat.ConnectionListener({
    onConnected: () => {
      console.log("ConnectionListener :: connected");
    },
    inConnecting: () => {
      console.log("ConnectionListener :: connecting");
    },
    onDisconnected: () => {
      console.log("ConnectionListener :: disconnected");
    },
    onFeatureThrottled: () => {
      console.log("ConnectionListener :: feature throttled");
    }
  })
);

Remove the listener when no longer needed:

CometChat.removeConnectionListener("UNIQUE_LISTENER_ID");

---

Next Steps

Receive Messages

Handle incoming messages in real-time

Typing Indicators

Show when users are typing

User Presence

Track online/offline status of users

Connection Status

Monitor SDK connection state changes