mapEventToState is deprecated and not working anymore

Question

i am Working on Flutter Chat Application and when i tried to implement the MessageBloc i found that mapEventToState is not Working anymore in Version 8.0 of Bloc

This is MessageEvent

import 'package:chat/chat.dart';
import 'package:equatable/equatable.dart';

abstract class MessageEvent extends Equatable {
  const MessageEvent();
  factory MessageEvent.onSubscribed(User user) => Subscribed(user);
  factory MessageEvent.onMessageSent(List<Message> messages) =>
      MessageSent(messages);
  @override
  List<Object?> get props => [];
}

class Subscribed extends MessageEvent {
  final User user;

  Subscribed(this.user);

  @override
  List<Object?> get props => [user];
}

class MessageSent extends MessageEvent {
  final List<Message> messages;
  MessageSent(this.messages);

  @override
  List<Object> get props => [messages];
}

class MessageReceived extends MessageEvent {
  MessageReceived(this.message);

  final Message message;

  @override
  List<Object> get props => [message];
}

And this is MessageState

import 'package:chat/chat.dart';
import 'package:equatable/equatable.dart';

abstract class MessageState extends Equatable {
  const MessageState();
  factory MessageState.initial() => MessageInitial();
  factory MessageState.sent(Message message) => MessageSentSuccesfully(message);
  factory MessageState.received(Message message) =>
      MessageReceivedSuccesfully(message);
  @override
  List<Object> get props => [];
}

class MessageInitial extends MessageState {}

class MessageSentSuccesfully extends MessageState {
  final Message message;
  const MessageSentSuccesfully(this.message);

  @override
  List<Object> get props => [message];
}

class MessageReceivedSuccesfully extends MessageState {
  final Message message;
  const MessageReceivedSuccesfully(this.message);

  @override
  List<Object> get props => [message];
}

and finally this is MessageBloc

import 'dart:async';

import 'package:bloc/bloc.dart';
import 'package:chat/chat.dart';
import 'package:flutter_newapp/src/blocs/message/message_event.dart';
import 'package:flutter_newapp/src/blocs/message/message_state.dart';

class MessageBloc extends Bloc<MessageEvent, MessageState> {
  final IMessageService _messageService;
  StreamSubscription? _subscription;
  MessageBloc(this._messageService) : super(MessageState.initial());

  @override
  Stream<MessageState> mapEventToState(MessageEvent event) async* {
    if (event is Subscribed) {
      await _subscription?.cancel();
      _subscription = _messageService
          .messages(activeUser: event.user)
          .listen((message) => add(MessageReceived(message)));
    }

    if (event is MessageReceived) {
      yield MessageState.received(event.message);
    }
    if (event is MessageSent) {
      final message = await _messageService.send(event.messages);
      yield MessageState.sent(message);
    }
  }

  @override
  Future<void> close() {
    _subscription?.cancel();
    _messageService.dispose();
    return super.close();
  }
}

Can anyone propose me a Solution to Rewrite the MessageBloc in the new Version of Bloc ?

i am trying to move from version 7.1 of Bloc to 8.1 or the Latest version of Bloc and try to learn the new implementation of Blocs in Flutter

mapEventToState is deprecated and not working anymore

0 Answers0