Flutter client of MqChat, a protocol built over MQTT for chatting purposes.


Use MQTT as a chat protocol, to create a modern chat application that supports all needed features. This is a flutter client of MqChat.

  • x Login
  • x Send/receive messages (text, image, vide, location, document, contact messages)
  • x Send Files
  • x Typing indicators
  • x Presence
  • x Group Chat
  • x Private Chat invitation

Getting started

Install the package flutter-mqchat:

flutter pub add flutter-mqchat


A full and rich example can be found in /example folder.

1. Login

User login using an existing account:

bool connected = await ChatApp.instance()!.clientHandler.connect(
        host: "broker.url.com",
        username: "user@test.com",
        password: "user_pass");

After a successful login, the mqtt client will receive updates. The first updates to be received are profile details, rooms that users is member of, ongoing invitations and messages (if message archiving is supported by the broker).

2. Listen to my profile changes

ChatApp.instance()!.archiveHandler.getUser().listen((user) {
      //insert/update user to database

3. Listen to rooms

Whenever the logged in user is added to a room (or room details changed), the room details will be added to the Conversations stream.

ChatApp.instance()!.archiveHandler.getAllConversations().listen((rooms) {
      //insert/update rooms on the Database

4. Listen to new messages

ChatApp.instance()!.messageReader.getChatMessages().listen((message) {
      var dbMessage = message.toDbMessage();
      // insert the message to the database
      // send chatmarker if the message is not mine

5. Listen to ChatMarkers

        .listen((markerMessage) {

      String messageId = markerMessage.referenceId;
      if (markerMessage.status == ChatMarker.displayed) {
          //update the database record
      } else if (markerMessage.status == ChatMarker.delivered) {
          //update the database record

6. Listen to new chat invitations

        .listen((invitation) {
          if(invitation.type == MessageType.EventInvitationRequest) {
            //new invitation request
            //insert invitation record to the database, notify the user
          if(invitation.type == MessageType.EventInvitationResponseAccept || invitation.type == MessageType.EventInvitationResponseReject) {
            //responded to invitation, update the local record and wait the server to sync the new contact (if accepted).
            //Do not insert a room, the user will receive a new room details triggered by getAllConversations()

7. Listen to invitatioin updates

We use this to listen to the invitations that the user has sent. It could be:

  • Info: When receive an affirmation that the invitation is sent
  • Error: When there is an error (like the user is not found)
        .listen((invitation) {
      if (invitation.invitationMessageType == InvitationMessageType.INFO) {
       //update the invitation record to be confirmed
      else if (invitation.invitationMessageType == InvitationMessageType.ERROR) {
        //notify the user, and delete the record in inserted

8. Send a text Message

ChatMessage newMessage = ChatMessage(
        id: "generated_random_id",
        type: MessageType.ChatText,
        text: "Hello there",
        roomId: "[room_id]",
        fromId: "[my_id]",//optional
        sendTime: DateTime.now().millisecondsSinceEpoch,
        fromName: "[my_name]");

8.1 Send the message as regular message

          .sendChatMessage(newMessage, "[room_id]");

8.2 Send the message as a reply to another message

ChatMessage replyToMessage = ...; //the message to reply to
          .replyToMessage(replyToMessage, newMessage, widget.contactChat.roomId);

9. Send File Message

          type: MessageType.ChatImage,//for example
          fileLocalPath: path,
          room: "[room_id]");

10. Send typing indicator

          .sendIsTyping(true, "[room_id]");

11. Listen to typing indicator

ChatApp.instance()!.messageReader.getTypingMessages().listen((event) {
    //using event.roomId and event.isTyping and event.fromId, update the ui state

12. Send new chat invitation

        .sendInvitation("[invitee_username]", "[invitation_random_id]");

Additional information

TODO: Tell users more about the package: where to find more information, how to contribute to the package, how to file issues, what response they can expect from the package authors, and more.