Events & Callbacks

Handle user interaction events, selection mode, and global UI Kit events with component-level and static event listeners.

The UI Kit provides two levels of event handling: component-level callbacks set directly on a View instance, and global events registered via static listener methods on event classes.

Component-Level Callbacks

Click Callbacks

Setter	Triggered When
setOnItemClick(OnItemClick<Conversation>)	User taps a list item
setOnItemLongClick(OnItemLongClick<Conversation>)	User long-presses a list item
setOnBackPressListener(OnBackPress)	User taps the back button
setOnSearchClickListener(OnSearchClick)	User taps the search icon

Kotlin

conversations.setOnItemClick { conversation, position ->
    // Navigate to chat screen
    openChat(conversation)
}

conversations.setOnItemLongClick { conversation, position ->
    // Show custom context menu
    showCustomMenu(conversation)
}

conversations.setOnBackPressListener {
    // Handle back navigation
    finish()
}

conversations.setOnSearchClickListener {
    // Open search screen
    openSearch()
}

Java

conversations.setOnItemClick((conversation, position) -> {
    // Navigate to chat screen
    openChat(conversation);
});

conversations.setOnItemLongClick((conversation, position) -> {
    // Show custom context menu
    showCustomMenu(conversation);
});

conversations.setOnBackPressListener(() -> {
    // Handle back navigation
    finish();
});

conversations.setOnSearchClickListener(() -> {
    // Open search screen
    openSearch();
});

Error Callback

Use setOnError to handle component-level errors:

Kotlin

conversations.setOnError { exception ->
    Log.e("Conversations", "Error: ${exception.message}")
}

Java

conversations.setOnError(exception -> {
    Log.e("Conversations", "Error: " + exception.getMessage());
});

Selection Mode

Enable single or multi-select on list components:

Method	Description
setSelectionMode(UIKitConstants.SelectionMode)	Set the selection mode: NONE, SINGLE, or MULTIPLE
setOnSelect(OnSelection<Conversation>)	Callback when selection changes
getSelectedConversations()	Get the list of currently selected conversations
clearSelection()	Clear all selections
selectConversation(Conversation, SelectionMode)	Programmatically select a conversation

Kotlin

// Enable multi-select mode
conversations.setSelectionMode(UIKitConstants.SelectionMode.MULTIPLE)

// Listen for selection changes
conversations.setOnSelect { selectedList ->
    updateToolbar(selectedList.size)
}

// Get selected items
val selected = conversations.getSelectedConversations()

// Clear selection
conversations.clearSelection()

Java

// Enable multi-select mode
conversations.setSelectionMode(UIKitConstants.SelectionMode.MULTIPLE);

// Listen for selection changes
conversations.setOnSelect(selectedList -> {
    updateToolbar(selectedList.size());
});

// Get selected items
List<Conversation> selected = conversations.getSelectedConversations();

// Clear selection
conversations.clearSelection();

Global Events

Global events are fired by the UI Kit when actions happen anywhere in the app. Register listeners using the static listener registration methods on each event class (addListener, addGroupListener, or addUserListener depending on the class).

Event Class	Fires When
CometChatConversationEvents	Conversation is deleted or updated
CometChatMessageEvents	Messages are sent, edited, deleted, or reacted to
CometChatGroupEvents	Groups are created, updated, members added/removed
CometChatUserEvents	Users are blocked/unblocked
CometChatUIEvents	UI-level events like opening chat, showing dialogs
CometChatCallEvents	Calls are initiated, accepted, rejected, or ended

Each listener is registered with a unique String tag so it can be removed later.

Component-Level vs Global Events

• Component-level callbacks (e.g., setOnItemClick) are set on a specific View instance and only fire for that component.
• Global events (e.g., CometChatMessageEvents.addListener) are static and fire regardless of which component triggered the action. Use them for cross-component coordination.

Kotlin

// Register a global message event listener
CometChatMessageEvents.addListener("unique-listener-id",
    object : CometChatMessageEvents() {
        override fun ccMessageSent(baseMessage: BaseMessage, status: Int) {
            // Handle sent message across the app
        }

        override fun onMessageDeleted(message: BaseMessage) {
            // Handle deleted message
        }
    }
)

// Remove the listener when done
CometChatMessageEvents.removeListener("unique-listener-id")

Java

// Register a global message event listener
CometChatMessageEvents.addListener("unique-listener-id",
    new CometChatMessageEvents() {
        @Override
        public void ccMessageSent(BaseMessage baseMessage, int status) {
            // Handle sent message across the app
        }

        @Override
        public void onMessageDeleted(BaseMessage message) {
            // Handle deleted message
        }
    }
);

// Remove the listener when done
CometChatMessageEvents.removeListener("unique-listener-id");

Related

• Events Reference — Full list of all event classes and their methods.
• Customization Overview — See all customization categories.