Skip to main content

Documentation Index

Fetch the complete documentation index at: https://www.cometchat.com/docs/llms.txt

Use this file to discover all available pages before exploring further.

// User Listener — online/offline presence
CometChat.addUserListener("ID", new CometChat.UserListener({
  onUserOnline: (user) => { },
  onUserOffline: (user) => { }
}));

// Message Listener — messages, typing, receipts, reactions
CometChat.addMessageListener("ID", new CometChat.MessageListener({
  onTextMessageReceived: (msg) => { },
  onMediaMessageReceived: (msg) => { },
  onTypingStarted: (indicator) => { },
  onMessagesRead: (receipt) => { }
}));

// Group Listener — member join/leave/kick/ban/scope changes
CometChat.addGroupListener("ID", new CometChat.GroupListener({
  onGroupMemberJoined: (action, joinedUser, joinedGroup) => { },
  onGroupMemberLeft: (action, leftUser, leftGroup) => { }
}));

// Call Listener — incoming/outgoing call events
CometChat.addCallListener("ID", new CometChat.CallListener({
  onIncomingCallReceived: (call) => { },
  onOutgoingCallAccepted: (call) => { }
}));

// Always clean up
CometChat.removeUserListener("ID");
CometChat.removeMessageListener("ID");
CometChat.removeGroupListener("ID");
CometChat.removeCallListener("ID");
Real-time listeners let you receive live events — messages, presence changes, group updates, and call signals — as they happen. The pattern is the same for all four listener types:
  1. Register a listener with a unique ID using addXListener()
  2. Handle events in the callback methods
  3. Remove the listener with removeXListener() when it’s no longer needed
Each listener ID must be unique. Re-registering with the same ID replaces the previous listener. Always remove listeners on component unmount to prevent memory leaks.
Always remove listeners when they’re no longer needed (e.g., on component unmount). Failing to remove listeners can cause memory leaks and duplicate event handling. For React Native, use useEffect cleanup functions to handle listener removal automatically.
CometChat provides 4 listeners viz.
  1. User Listener
  2. Group Listener
  3. Message Listener
  4. Call Listener

User Listener

Receive online/offline presence events for users.
MethodInformation
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:
const listenerID: string = "UNIQUE_LISTENER_ID";
CometChat.addUserListener(
  listenerID,
  new CometChat.UserListener({
    onUserOnline: (onlineUser: CometChat.User) => {
      console.log("On User Online:", { onlineUser });
    },
    onUserOffline: (offlineUser: CometChat.User) => {
      console.log("On User Offline:", { offlineUser });
    },
  })
);
Remove the listener when no longer needed:
let listenerID: string = "UNIQUE_LISTENER_ID";
CometChat.removeUserListener(listenerID);

Group Listener

Receive events when group members join, leave, are kicked/banned, or have their scope changed.
MethodInformation
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 unbanned 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:
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,
      });
    },
  })
);
Remove the listener when no longer needed:
let listenerID: string = "UNIQUE_LISTENER_ID";
CometChat.removeGroupListener(listenerID);

Message Listener

Receive events for incoming messages, typing indicators, read/delivery receipts, message edits/deletes, reactions, and interactive messages.
MethodInformation
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.
onInteractiveMessageReceived(message: CometChat.InteractiveMessage)This event is triggered when an Interactive Message is received.
onInteractionGoalCompleted(receipt: CometChat.InteractionReceipt)This event is triggered when an interaction Goal is achieved.
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 removed from a message in a user/group conversation.
To add the MessageListener:
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 Deleted", message);
    },
    onMessageEdited: (message: CometChat.BaseMessage) => {
      console.log("Message Edited", message);
    },
    onInteractiveMessageReceived: (message: CometChat.InteractiveMessage) => {
      console.log("Interactive Message received", message);
    },
    onInteractionGoalCompleted: (receipt: CometChat.InteractionReceipt) => {
      console.log("Interaction goal completed", receipt);
    },
    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);
    },
  })
);
Remove the listener when no longer needed:
let listenerID: string = "UNIQUE_LISTENER_ID";
CometChat.removeMessageListener(listenerID);

Call Listener

Receive events for incoming and outgoing call state changes.
MethodInformation
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
To add the CallListener:
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);
    },
  })
);
Remove the listener when no longer needed:
let listenerID: string = "UNIQUE_LISTENER_ID";
CometChat.removeCallListener(listenerID);

Next Steps

User Presence

Track when users come online or go offline

Receive Messages

Handle incoming messages in real time

Typing Indicators

Show when users are typing

Connection Status

Monitor SDK connection state changes