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Architecture

The UI Kit is a set of independent components that compose into chat layouts. A typical two-panel layout uses four core components:
  • CometChatConversations — sidebar listing recent conversations (users and groups)
  • CometChatMessageHeader — toolbar showing avatar, name, online status, and typing indicator
  • CometChatMessageList — scrollable message feed with reactions, receipts, and threads
  • CometChatMessageComposer — rich text input with attachments, mentions, and voice notes
Data flow: selecting a conversation in CometChatConversations yields a CometChat.User or CometChat.Group object. That object is passed as a prop (user or group) to CometChatMessageHeader, CometChatMessageList, and CometChatMessageComposer. The message components use the SDK internally — CometChatMessageComposer sends messages, CometChatMessageList receives them via real-time listeners. Components communicate through a publish/subscribe event bus (CometChatMessageEvents, CometChatConversationEvents, CometChatGroupEvents, etc.). A component emits events that other components or application code can subscribe to without direct references. See Events for the full list. Each component accepts callback props (on<Event>), view slot props (<slot>View) for replacing UI sections, RequestBuilder props for data filtering, and CSS variable overrides on .cometchat-<component> classes.

Component Catalog

All components are imported from @cometchat/chat-uikit-react.

Conversations and Lists

Messages

Calling

Search and AI

Component API Pattern

All components share a consistent API surface.

Actions

Actions control component behavior. They split into two categories: Predefined Actions are built into the component and execute automatically on user interaction (e.g., clicking send dispatches the message). No configuration needed. User-Defined Actions are callback props that fire on specific events. Override them to customize behavior:

Events

Events enable decoupled communication between components. A component emits events that other parts of the application can subscribe to without direct references.
Each component page documents its emitted events in the Events section.

Filters

List-based components accept RequestBuilder props to control which data loads:

Custom View Slots

Components expose named view slots to replace sections of the default UI:

CSS Overrides

Every component has a root CSS class (.cometchat-<component>) for style customization:

Next Steps

Core Features

Chat features included out of the box

Theming

Customize colors, fonts, and styles

Extensions

Add-on features like polls, stickers, and translation

Guides

Task-oriented tutorials for common patterns