Real-Time Events

The UCometChatSubsystem exposes five multicast delegates that fire whenever the server pushes a real-time update. All delegates are guaranteed to fire on the Game Thread, so you can safely update UI directly.

Event Flow

Bind delegates before calling Login. Events that arrive between Login completing and your bindings being set up will be missed.

Binding Delegates

Blueprint
C++

Get a reference to the CometChat Subsystem
Drag off the Subsystem pin and search for the delegate name (e.g., On Message Received)
Select Bind Event to wire it to a custom event node
The custom event automatically gets the correct parameter type

void AMyActor::BeginPlay()
{
    Super::BeginPlay();

    UCometChatSubsystem* Chat = GetGameInstance()->GetSubsystem<UCometChatSubsystem>();

    Chat->OnMessageReceived.AddDynamic(this, &AMyActor::HandleMessage);
    Chat->OnPresenceChanged.AddDynamic(this, &AMyActor::HandlePresence);
    Chat->OnTypingChanged.AddDynamic(this, &AMyActor::HandleTyping);
    Chat->OnReceiptReceived.AddDynamic(this, &AMyActor::HandleReceipt);
    Chat->OnConnectionStateChanged.AddDynamic(this, &AMyActor::HandleConnection);
}

OnMessageReceived

Fires when a new message arrives in any conversation (1:1 or group).

Payload	Type
`Message`	`FCometChatMessage`

Blueprint
C++

The custom event receives an FCometChatMessage. Use ReceiverType to check if it’s a user (1:1) or group message, and ConversationId to route it to the right chat window.

void AMyActor::HandleMessage(const FCometChatMessage& Message)
{
    if (Message.ReceiverType == TEXT("group"))
    {
        UE_LOG(LogTemp, Log, TEXT("[Group %s] %s: %s"),
            *Message.ConversationId, *Message.SenderName, *Message.Text);
    }
    else
    {
        UE_LOG(LogTemp, Log, TEXT("[DM] %s: %s"),
            *Message.SenderName, *Message.Text);
    }
}

OnPresenceChanged

Fires when a user’s online status changes.

Payload	Type
`Presence`	`FCometChatPresence`

Blueprint
C++

The custom event receives an FCometChatPresence with Uid, Status (an ECometChatPresenceStatus enum), and LastActiveAt.

void AMyActor::HandlePresence(const FCometChatPresence& Presence)
{
    FString StatusStr;
    switch (Presence.Status)
    {
    case ECometChatPresenceStatus::Online:  StatusStr = TEXT("Online");  break;
    case ECometChatPresenceStatus::Offline: StatusStr = TEXT("Offline"); break;
    case ECometChatPresenceStatus::Away:    StatusStr = TEXT("Away");    break;
    }

    UE_LOG(LogTemp, Log, TEXT("%s is now %s"), *Presence.Uid, *StatusStr);
}

For more details, see Users → User Presence.

OnTypingChanged

Fires when a user starts or stops typing in a conversation.

Payload	Type
`Event`	`FCometChatTypingEvent`

Blueprint
C++

The custom event receives an FCometChatTypingEvent with Uid, ConversationId, and bIsTyping.

void AMyActor::HandleTyping(const FCometChatTypingEvent& Event)
{
    if (Event.bIsTyping)
    {
        UE_LOG(LogTemp, Log, TEXT("%s is typing in %s..."),
            *Event.Uid, *Event.ConversationId);
    }
    else
    {
        UE_LOG(LogTemp, Log, TEXT("%s stopped typing in %s"),
            *Event.Uid, *Event.ConversationId);
    }
}

For more details, see Typing Indicators.

OnReceiptReceived

Fires when a message is delivered to or read by the recipient.

Payload	Type
`Event`	`FCometChatReceiptEvent`

Blueprint
C++

The custom event receives an FCometChatReceiptEvent with MessageId, Uid, Status (delivered or read), and Timestamp.

void AMyActor::HandleReceipt(const FCometChatReceiptEvent& Event)
{
    UE_LOG(LogTemp, Log, TEXT("Message %s was %s by %s"),
        *Event.MessageId, *Event.Status, *Event.Uid);
}

For more details, see Delivery & Read Receipts.

OnConnectionStateChanged

Fires when the WebSocket connection state changes.

Payload	Type
`State`	`ECometChatConnectionState`

Value	Meaning
`Connected`	WebSocket is active and receiving events
`Disconnected`	Connection lost
`Reconnecting`	SDK is attempting to reconnect automatically

Blueprint
C++

The custom event receives an ECometChatConnectionState enum value.

void AMyActor::HandleConnection(ECometChatConnectionState State)
{
    switch (State)
    {
    case ECometChatConnectionState::Connected:
        UE_LOG(LogTemp, Log, TEXT("Connected to CometChat"));
        break;
    case ECometChatConnectionState::Disconnected:
        UE_LOG(LogTemp, Warning, TEXT("Disconnected from CometChat"));
        break;
    case ECometChatConnectionState::Reconnecting:
        UE_LOG(LogTemp, Warning, TEXT("Reconnecting..."));
        break;
    }
}

For more details, see Connection Status.

Delegate Summary

Delegate	Payload	Use Case
`OnMessageReceived`	`FCometChatMessage`	Display new messages in chat UI
`OnPresenceChanged`	`FCometChatPresence`	Update online/offline indicators
`OnTypingChanged`	`FCometChatTypingEvent`	Show “typing…” animations
`OnReceiptReceived`	`FCometChatReceiptEvent`	Show delivery/read checkmarks
`OnConnectionStateChanged`	`ECometChatConnectionState`	Show connection status banners

Authentication

Messaging

Users & Groups

Reference

Event Flow

Binding Delegates

OnMessageReceived

OnPresenceChanged

OnTypingChanged

OnReceiptReceived

OnConnectionStateChanged

Delegate Summary

​Event Flow

​Binding Delegates

​OnMessageReceived

​OnPresenceChanged

​OnTypingChanged

​OnReceiptReceived

​OnConnectionStateChanged

​Delegate Summary

Event Flow

Binding Delegates

OnMessageReceived

OnPresenceChanged

OnTypingChanged

OnReceiptReceived

OnConnectionStateChanged

Delegate Summary