Core Features - CometChat Docs

CometChat UI Kit provides production-ready components that work together to deliver a complete chat experience. This guide shows how to implement each core feature with copy-paste code examples.

Instant Messaging

Send and receive text messages in real-time.

import UIKit
import CometChatUIKitSwift
import CometChatSDK

class ChatViewController: UIViewController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // For one-on-one chat
        let messagesVC = CometChatMessages()
        
        // Set the user to chat with
        CometChat.getUser(UID: "user-123") { user in
            DispatchQueue.main.async {
                messagesVC.set(user: user)
                self.navigationController?.pushViewController(messagesVC, animated: true)
            }
        } onError: { error in
            print("Error: \(error?.errorDescription ?? "")")
        }
    }
}

Components Used:

MessageComposer - Text input and send button
MessageList - Displays sent and received messages
Messages - Complete messaging screen (includes both)

Share images, videos, audio files, and documents.

import UIKit
import CometChatUIKitSwift
import CometChatSDK

class MediaChatViewController: UIViewController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        let messagesVC = CometChatMessages()
        
        // The message composer automatically includes media sharing options
        // Users can tap the attachment button to share:
        // - Photos from library
        // - Camera capture
        // - Documents
        // - Audio files
        
        CometChat.getUser(UID: "user-123") { user in
            DispatchQueue.main.async {
                messagesVC.set(user: user)
                self.navigationController?.pushViewController(messagesVC, animated: true)
            }
        } onError: { error in
            print("Error: \(error?.errorDescription ?? "")")
        }
    }
    
    // Send media programmatically
    func sendImage(to receiverUID: String, imageURL: URL) {
        let mediaMessage = MediaMessage(
            receiverUid: receiverUID,
            fileurl: imageURL.absoluteString,
            messageType: .image,
            receiverType: .user
        )
        
        CometChat.sendMediaMessage(message: mediaMessage) { message in
            print("Image sent successfully")
        } onError: { error in
            print("Error sending image: \(error?.errorDescription ?? "")")
        }
    }
}

Supported Media Types:

Type	Bubble Component
Images	Image Bubble
Videos	Video Bubble
Audio	Audio Bubble
Files	File Bubble

Read Receipts

Show when messages are delivered and read.

import UIKit
import CometChatUIKitSwift
import CometChatSDK

class ReceiptsViewController: UIViewController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // Read receipts are enabled by default
        let messagesVC = CometChatMessages()
        
        // To hide receipts:
        // messagesVC.hideReceipts = true
        
        CometChat.getUser(UID: "user-123") { user in
            DispatchQueue.main.async {
                messagesVC.set(user: user)
                self.navigationController?.pushViewController(messagesVC, animated: true)
            }
        } onError: { error in
            print("Error: \(error?.errorDescription ?? "")")
        }
    }
    
    // View detailed message information
    func showMessageInfo(for message: BaseMessage) {
        let messageInfo = CometChatMessageInformation()
        messageInfo.set(message: message)
        navigationController?.pushViewController(messageInfo, animated: true)
    }
}

Receipt States:

✓ Sent - Message sent to server
✓✓ Delivered - Message delivered to recipient’s device
✓✓ (blue) Read - Recipient has seen the message

Components Used:

Conversations - Shows receipt status on last message
MessageList - Shows receipts on each message
MessageInformation - Detailed delivery/read info

Mark As Unread

Let users mark messages as unread to revisit later.

import UIKit
import CometChatUIKitSwift
import CometChatSDK

class UnreadMessagesViewController: UIViewController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        let messagesVC = CometChatMessages()
        
        // Enable starting from first unread message
        messagesVC.scrollToUnreadMessages = true
        
        CometChat.getUser(UID: "user-123") { user in
            DispatchQueue.main.async {
                messagesVC.set(user: user)
                self.navigationController?.pushViewController(messagesVC, animated: true)
            }
        } onError: { error in
            print("Error: \(error?.errorDescription ?? "")")
        }
    }
    
    // Mark a message as unread programmatically
    func markAsUnread(message: BaseMessage) {
        CometChat.markAsUnread(
            baseMessage: message
        ) { _ in
            print("Marked as unread")
        } onError: { error in
            print("Error: \(error?.errorDescription ?? "")")
        }
    }
}

Typing Indicators

Show when users are typing in real-time.

import UIKit
import CometChatUIKitSwift
import CometChatSDK

class TypingIndicatorViewController: UIViewController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // Typing indicators are enabled by default in:
        // - CometChatConversations (shows "typing..." in conversation list)
        // - CometChatMessageHeader (shows "typing..." below user name)
        
        let messagesVC = CometChatMessages()
        
        CometChat.getUser(UID: "user-123") { user in
            DispatchQueue.main.async {
                messagesVC.set(user: user)
                self.navigationController?.pushViewController(messagesVC, animated: true)
            }
        } onError: { error in
            print("Error: \(error?.errorDescription ?? "")")
        }
    }
    
    // Send typing indicator manually
    func startTyping(to receiverUID: String) {
        let typingIndicator = TypingIndicator(
            receiverID: receiverUID,
            receiverType: .user
        )
        CometChat.startTyping(indicator: typingIndicator)
    }
    
    func stopTyping(to receiverUID: String) {
        let typingIndicator = TypingIndicator(
            receiverID: receiverUID,
            receiverType: .user
        )
        CometChat.endTyping(indicator: typingIndicator)
    }
}

Components Used:

Conversations - Shows typing in conversation list
MessageHeader - Shows typing below user/group name

User Presence

Display online/offline status for users.

import UIKit
import CometChatUIKitSwift
import CometChatSDK

class PresenceViewController: UIViewController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // User presence is shown automatically in:
        // - CometChatConversations (green dot for online users)
        // - CometChatMessageHeader (shows "Online" or "Last seen")
        // - CometChatUsers (green dot for online users)
        // - CometChatGroupMembers (green dot for online members)
        
        let conversations = CometChatConversations()
        
        // To hide user status:
        // conversations.hideUserStatus = true
        
        navigationController?.pushViewController(conversations, animated: true)
    }
    
    // Listen for presence changes
    func listenForPresenceChanges() {
        CometChat.addUserListener("presence-listener", self)
    }
}

extension PresenceViewController: CometChatUserDelegate {
    func onUserOnline(user: User) {
        print("\(user.name ?? "") is now online")
    }
    
    func onUserOffline(user: User) {
        print("\(user.name ?? "") went offline")
    }
}

Reactions

Let users react to messages with emojis.

import UIKit
import CometChatUIKitSwift
import CometChatSDK

class ReactionsViewController: UIViewController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // Reactions are enabled by default
        // Users can long-press a message to add reactions
        
        let messagesVC = CometChatMessages()
        
        CometChat.getUser(UID: "user-123") { user in
            DispatchQueue.main.async {
                messagesVC.set(user: user)
                self.navigationController?.pushViewController(messagesVC, animated: true)
            }
        } onError: { error in
            print("Error: \(error?.errorDescription ?? "")")
        }
    }
    
    // Add reaction programmatically
    func addReaction(to message: BaseMessage, emoji: String) {
        CometChat.addReaction(
            messageId: message.id,
            reaction: emoji
        ) { message in
            print("Reaction added")
        } onError: { error in
            print("Error: \(error?.errorDescription ?? "")")
        }
    }
    
    // Remove reaction
    func removeReaction(from message: BaseMessage, emoji: String) {
        CometChat.removeReaction(
            messageId: message.id,
            reaction: emoji
        ) { message in
            print("Reaction removed")
        } onError: { error in
            print("Error: \(error?.errorDescription ?? "")")
        }
    }
}

Mentions

Tag users in messages with @mentions.

import UIKit
import CometChatUIKitSwift
import CometChatSDK

class MentionsViewController: UIViewController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // Mentions are enabled by default
        // Type @ in the composer to see mention suggestions
        
        let messagesVC = CometChatMessages()
        
        CometChat.getGroup(GUID: "group-123") { group in
            DispatchQueue.main.async {
                messagesVC.set(group: group)
                self.navigationController?.pushViewController(messagesVC, animated: true)
            }
        } onError: { error in
            print("Error: \(error?.errorDescription ?? "")")
        }
    }
    
    // Send message with mention programmatically
    func sendMessageWithMention(to groupID: String, mentionedUser: User) {
        let textMessage = TextMessage(
            receiverUid: groupID,
            text: "Hey @\(mentionedUser.name ?? ""), check this out!",
            receiverType: .group
        )
        
        // Add mentioned users
        textMessage.mentionedUsers = [mentionedUser]
        
        CometChat.sendTextMessage(message: textMessage) { message in
            print("Message with mention sent")
        } onError: { error in
            print("Error: \(error?.errorDescription ?? "")")
        }
    }
}

Threaded Conversations

Reply to specific messages in threads.

import UIKit
import CometChatUIKitSwift
import CometChatSDK

class ThreadedMessagesViewController: UIViewController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // Threaded messages are enabled by default
        // Users can tap "Reply in thread" on any message
        
        let messagesVC = CometChatMessages()
        
        CometChat.getUser(UID: "user-123") { user in
            DispatchQueue.main.async {
                messagesVC.set(user: user)
                self.navigationController?.pushViewController(messagesVC, animated: true)
            }
        } onError: { error in
            print("Error: \(error?.errorDescription ?? "")")
        }
    }
    
    // Open thread view for a message
    func openThread(for parentMessage: BaseMessage, user: User) {
        let threadedMessages = CometChatThreadedMessages()
        threadedMessages.set(parentMessage: parentMessage)
        threadedMessages.set(user: user)
        navigationController?.pushViewController(threadedMessages, animated: true)
    }
    
    // Send reply in thread programmatically
    func sendThreadReply(parentMessage: BaseMessage, text: String) {
        let reply = TextMessage(
            receiverUid: parentMessage.receiverUid,
            text: text,
            receiverType: parentMessage.receiverType
        )
        reply.parentMessageId = parentMessage.id
        
        CometChat.sendTextMessage(message: reply) { message in
            print("Thread reply sent")
        } onError: { error in
            print("Error: \(error?.errorDescription ?? "")")
        }
    }
}

Component Used:

ThreadedMessages - Displays thread replies

Group Chat

Create and manage group conversations.

import UIKit
import CometChatUIKitSwift
import CometChatSDK

class GroupChatViewController: UIViewController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        showGroupsList()
    }
    
    // Show all groups
    func showGroupsList() {
        let groups = CometChatGroups()
        
        groups.set(onItemClick: { [weak self] group, _ in
            self?.openGroupChat(group: group)
        })
        
        navigationController?.pushViewController(groups, animated: true)
    }
    
    // Open chat for a group
    func openGroupChat(group: Group) {
        let messagesVC = CometChatMessages()
        messagesVC.set(group: group)
        navigationController?.pushViewController(messagesVC, animated: true)
    }
    
    // Create a new group
    func createGroup(name: String, type: CometChat.groupType) {
        let group = Group(
            guid: UUID().uuidString,
            name: name,
            groupType: type,
            password: nil
        )
        
        CometChat.createGroup(group: group) { createdGroup in
            print("Group created: \(createdGroup.name ?? "")")
            DispatchQueue.main.async {
                self.openGroupChat(group: createdGroup)
            }
        } onError: { error in
            print("Error: \(error?.errorDescription ?? "")")
        }
    }
    
    // Join a public group
    func joinGroup(guid: String) {
        CometChat.joinGroup(
            GUID: guid,
            groupType: .public,
            password: nil
        ) { group in
            print("Joined group: \(group.name ?? "")")
            DispatchQueue.main.async {
                self.openGroupChat(group: group)
            }
        } onError: { error in
            print("Error: \(error?.errorDescription ?? "")")
        }
    }
}

Related Guide: Groups

Quoted Reply

Reply to specific messages with context.

import UIKit
import CometChatUIKitSwift
import CometChatSDK

class QuotedReplyViewController: UIViewController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // Quoted reply is enabled by default
        // Users can swipe right on a message or tap "Reply" in message actions
        
        let messagesVC = CometChatMessages()
        
        CometChat.getUser(UID: "user-123") { user in
            DispatchQueue.main.async {
                messagesVC.set(user: user)
                self.navigationController?.pushViewController(messagesVC, animated: true)
            }
        } onError: { error in
            print("Error: \(error?.errorDescription ?? "")")
        }
    }
}

Search

Search across conversations and messages.

import UIKit
import CometChatUIKitSwift
import CometChatSDK

class SearchViewController: UIViewController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // Search is available in:
        // - CometChatConversations (search bar at top)
        // - CometChatMessageHeader (search button)
        
        let conversations = CometChatConversations()
        
        // Search is enabled by default
        // To hide search:
        // conversations.hideSearch = true
        
        navigationController?.pushViewController(conversations, animated: true)
    }
    
    // Open dedicated search screen
    func openSearch() {
        let search = CometChatSearch()
        navigationController?.pushViewController(search, animated: true)
    }
}

Components Used:

Search - Dedicated search screen
MessageHeader - Search within conversation
Conversations - Search conversations

Moderation

Automatically filter inappropriate content.

import UIKit
import CometChatUIKitSwift
import CometChatSDK

class ModerationViewController: UIViewController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // Moderation is handled automatically based on your
        // CometChat dashboard settings
        
        // Blocked messages are displayed appropriately
        // based on your moderation rules
        
        let messagesVC = CometChatMessages()
        
        CometChat.getUser(UID: "user-123") { user in
            DispatchQueue.main.async {
                messagesVC.set(user: user)
                self.navigationController?.pushViewController(messagesVC, animated: true)
            }
        } onError: { error in
            print("Error: \(error?.errorDescription ?? "")")
        }
    }
}

Configure moderation rules in your CometChat Dashboard.

Report Message

Allow users to report inappropriate messages.

import UIKit
import CometChatUIKitSwift
import CometChatSDK

class ReportMessageViewController: UIViewController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // Report message is available in message actions
        // Users can long-press a message and select "Report"
        
        let messagesVC = CometChatMessages()
        
        CometChat.getUser(UID: "user-123") { user in
            DispatchQueue.main.async {
                messagesVC.set(user: user)
                self.navigationController?.pushViewController(messagesVC, animated: true)
            }
        } onError: { error in
            print("Error: \(error?.errorDescription ?? "")")
        }
    }
}

View and manage reported messages in Flagged Messages.

Complete Chat App Example

Here’s a production-ready implementation combining all core features:

import UIKit
import CometChatUIKitSwift
import CometChatSDK

@main
class AppDelegate: UIResponder, UIApplicationDelegate {
    
    var window: UIWindow?
    
    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        
        // Initialize CometChat
        let uiKitSettings = UIKitSettings()
            .set(appID: "YOUR_APP_ID")
            .set(authKey: "YOUR_AUTH_KEY")
            .set(region: "YOUR_REGION")
            .build()
        
        CometChatUIKit.init(uiKitSettings: uiKitSettings) { result in
            switch result {
            case .success:
                self.loginAndShowChat()
            case .failure(let error):
                print("Init failed: \(error.localizedDescription)")
            }
        }
        
        return true
    }
    
    private func loginAndShowChat() {
        CometChatUIKit.login(uid: "user-123") { result in
            switch result {
            case .success(let user):
                print("Logged in as: \(user.name ?? "")")
                DispatchQueue.main.async {
                    self.showMainScreen()
                }
            case .failure(let error):
                print("Login failed: \(error.localizedDescription)")
            }
        }
    }
    
    private func showMainScreen() {
        let tabBar = MainTabBarController()
        window?.rootViewController = tabBar
        window?.makeKeyAndVisible()
    }
}

class MainTabBarController: UITabBarController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // Conversations Tab
        let conversationsNav = UINavigationController()
        let conversations = CometChatConversations()
        conversations.set(onItemClick: { [weak conversationsNav] conversation, _ in
            let messagesVC = CometChatMessages()
            if let user = conversation.conversationWith as? User {
                messagesVC.set(user: user)
            } else if let group = conversation.conversationWith as? Group {
                messagesVC.set(group: group)
            }
            conversationsNav?.pushViewController(messagesVC, animated: true)
        })
        conversationsNav.setViewControllers([conversations], animated: false)
        conversationsNav.tabBarItem = UITabBarItem(
            title: "Chats",
            image: UIImage(systemName: "message"),
            selectedImage: UIImage(systemName: "message.fill")
        )
        
        // Users Tab
        let usersNav = UINavigationController()
        let users = CometChatUsers()
        users.set(onItemClick: { [weak usersNav] user, _ in
            let messagesVC = CometChatMessages()
            messagesVC.set(user: user)
            usersNav?.pushViewController(messagesVC, animated: true)
        })
        usersNav.setViewControllers([users], animated: false)
        usersNav.tabBarItem = UITabBarItem(
            title: "Users",
            image: UIImage(systemName: "person.2"),
            selectedImage: UIImage(systemName: "person.2.fill")
        )
        
        // Groups Tab
        let groupsNav = UINavigationController()
        let groups = CometChatGroups()
        groups.set(onItemClick: { [weak groupsNav] group, _ in
            let messagesVC = CometChatMessages()
            messagesVC.set(group: group)
            groupsNav?.pushViewController(messagesVC, animated: true)
        })
        groupsNav.setViewControllers([groups], animated: false)
        groupsNav.tabBarItem = UITabBarItem(
            title: "Groups",
            image: UIImage(systemName: "person.3"),
            selectedImage: UIImage(systemName: "person.3.fill")
        )
        
        viewControllers = [conversationsNav, usersNav, groupsNav]
    }
}

Feature Summary

Feature	Component	Enabled by Default
Text Messaging	Messages	✅
Media Sharing	MessageComposer	✅
Read Receipts	MessageList	✅
Typing Indicators	MessageHeader	✅
User Presence	Conversations	✅
Reactions	MessageList	✅
Mentions	MessageComposer	✅
Threads	ThreadedMessages	✅
Search	Search	✅
Moderation	Dashboard Config	Configure in Dashboard

​Instant Messaging

​Media Sharing

​Read Receipts

​Mark As Unread

​Typing Indicators

​User Presence

​Reactions

​Mentions

​Threaded Conversations

​Group Chat

​Quoted Reply

​Search

​Moderation

​Report Message

​Complete Chat App Example

​Feature Summary

Instant Messaging

Media Sharing

Read Receipts

Mark As Unread

Typing Indicators

User Presence

Reactions

Mentions

Threaded Conversations

Group Chat

Quoted Reply

Search

Moderation

Report Message

Complete Chat App Example

Feature Summary