Flutter SDK

Headless client for your own UI. Prefer widgets? Use the Flutter UI Kit.

Before code: mint a session token on your server. Never ship sk_* in the app.
Guided path: Quick start → Flutter SDK.

Fast path

Do this in order — most integrations are these five steps.

1. Install

flutter pub add sendsar_chat

2. Connect

import 'dart:convert';
import 'package:http/http.dart' as http;
import 'package:sendsar_chat/sendsar_chat.dart';

Future<SessionResponse> fetchChatSession() async {
  final res = await http.post(
    Uri.parse('https://your-app.com/api/chat/session'),
    headers: {'Cookie': '…'},
  );
  if (res.statusCode < 200 || res.statusCode >= 300) {
    throw Exception(res.body);
  }
  return SessionResponse.fromJson(jsonDecode(res.body) as Map<String, dynamic>);
}

final session = await fetchChatSession();
final client = Sendsar.init(SendsarInitOptions(apiUrl: session.apiUrl));
await client.connect(ConnectOptions(
  userId: session.chatUserId,
  token: session.token,
));

3. Conversation list (inbox)

final rooms = await client.listRooms();
setConversations(rooms); // ConversationListPage

client.on<Message>(SocketEvent.newMessage, (msg) {
  bumpConversation(msg); // preview, time, sort, unread
});

4. Message thread (open room)

Create in ChatPage; destroy in dispose.

final sub = createRoomSubscription(
  client,
  RoomSubscriptionOptions(
    roomId: openRoomId,
    userId: session.chatUserId,
    onInitialMessages: (messages, peerLastReadAt, [nextCursor]) {
      setMessages(messages);
    },
    onMessage: (msg) {
      appendById(msg);
      bumpConversation(msg);
    },
    onMessageUpdated: (msg) => replaceById(msg),
  ),
);

// dispose:
sub.destroy();

5. Send

final sent = await client.sendMessage(openRoomId, SendMessageParams(
  parts: [MessagePart(type: 'text', text: 'Hello')],
));
appendById(sent);
bumpConversation(sent);

---

Screens (what to update)

Screen	Shows	Your widget
Conversation list	Rooms, last message, unread	ConversationListPage
Message thread	Bubbles + composer for one roomId	ChatPage / MessageList

Also common: Room info, Call UI.

Happens	Conversation list	Message thread
createRoom	Add row	Optional: open it
New message	Bump preview / unread	Append if that room is open
Edit / delete / reaction / pin	Preview if latest	Replace by id
forwardMessage	Bump targets	Append in open target
deleteConversation	Remove row	Pop if open
clearHistory	Clear preview	Empty list
Members change	Optional subtitle	Room info
Incoming call	Optional badge	Call UI

WARNING

messageUpdated → replace by id. Never append a second bubble.

---

Messaging APIs

Create room & send text

final room = await client.createRoom(CreateRoomParams(
  externalId: 'dm:${session.chatUserId}:user_bob',
  participants: [
    CreateRoomParticipant(id: session.chatUserId),
    CreateRoomParticipant(id: 'user_bob'),
  ],
));
// → Conversation list: add row

final sent = await client.sendMessage(room.id, SendMessageParams(
  parts: [MessagePart(type: 'text', text: 'Hello')],
));
// → Thread: append · List: bump · Event: newMessage

Edit, delete, reply

await client.updateMessage(roomId, messageId, UpdateMessageParams(
  parts: [MessagePart(type: 'text', text: 'Updated')],
)); // → replace · messageUpdated

await client.deleteMessage(roomId, messageId);
// → replace (deletedAt)

await client.sendMessage(roomId, SendMessageParams(
  parts: [MessagePart(type: 'text', text: 'Replying!')],
  parentMessageId: messageId,
)); // → append · newMessage

Reactions

await client.toggleReaction(
  roomId,
  messageId,
  ToggleReactionParams(emoji: '👍'),
); // → replace (reactions) · messageUpdated

Pin & forward

await client.pinMessage(roomId, messageId);
await client.unpinMessage(roomId, messageId);

await client.forwardMessage(roomId, messageId, ForwardMessageParams(
  targetRoomIds: [otherRoomId],
)); // → target rooms: newMessage + bump list

Send files

final message = await client.sendFileMessage(
  roomId,
  bytes: fileBytes,
  filename: 'photo.jpg',
  mediaType: 'image/jpeg',
); // → append · hydrate URLs for previews

Members & conversation

await client.addParticipant(roomId, AddParticipantParams(userId: otherUserId));
await client.removeParticipant(roomId, otherUserId);
client.on(SocketEvent.roomParticipantsChanged, (ev) {
  if (ev.roomId == roomId) refreshMembers();
});

await client.deleteConversation(roomId);
await client.clearHistory(roomId);

---

Voice & video (optional)

Enable in the dashboard, then flutter pub add sendsar_call (+ mic/camera permissions).

import 'package:sendsar_call/sendsar_call.dart';

final calls = CallClient(CallClientOptions(chat: client));
calls.on('incoming', (invite) => showIncomingCall(invite));
calls.on('localTrack', (e) { /* bind */ });
calls.on('remoteTrack', (e) { /* bind */ });
await calls.start(room.id, const CallStartOptions(type: 'video'));

---

Checklist

• [ ] Session from your BFF — no sk_* in the app
• [ ] Conversation list: listRooms + newMessage bumps
• [ ] Message thread: createRoomSubscription (destroy on leave)
• [ ] messageUpdated → replace by id
• [ ] Files: hydrate access URLs for previews
• [ ] Calls (if needed): sendsar_call + dashboard flag

Next

• Issue session tokens · JavaScript SDK · API Reference