async_cubits 0.1.0+2

A set of cubits that can be used to handle async operations in a simple, consistent way.

async_cubits

A package that provides set of cubits for making asynchronous operations in simpler, consistent way.

Installation 💻

❗ In order to start using Async Cubits you must have the Flutter SDK installed on your machine.

flutter pub add async_cubits

---

Usage 🚀

Importing the package

import 'package:async_cubits/async_cubits.dart';

Using a FutureCubit

FutureCubits are a type of Cubit that can be used to make asynchronous operations that return a value. E.g. fetching data from API.

class GetUserCubit extends FutureCubit<User> {
  final UserRepository _userRepository;

  GetUserCubit(this._userRepository);
  
  @override
  Future<User> future() => _userRepository.getUser();
}

Integrating with UI widgets

In your UI you can use BlocProvider and BlocBuilder to load and access the data.

BlocProvider(
  create: (context) => GetUserCubit(
    context.read<UserRepository>(),
  )..load(), // load the data when the cubit is created
  child: BlocBuilder<GetUserCubit, AsyncState<User>>(
    builder: (context, state) {
      return state.when(
        loading: () => CircularProgressIndicator(),
        error: (error) => Text(error),
        data: (user) => Text(user.name),
      );
    },
  ),
);

Triggering refresh

If you want to trigger refresh of the data you can call the refresh method on the cubit.

ElevatedButton(
  onPressed: () => context.read<GetUserCubit>().refresh(),
  child: Text('Refresh'),
),

By default, the AsyncValue.when method will use data callback if the data was previously fetched.

So according to the example above, if the data was fetched successfully, the Text(user.name) will be rendered and no loading indicator will be shown when the cubit is refreshed.

Loading/refreshing with new arguments

To load/refresh the data with new arguments that are passed to the future method, use FutureWithArgsCubit.

class GetUserByIdCubit extends FutureWithArgsCubit<int, User> {
  final UserRepository _userRepository;

  GetUserCubit(this._userRepository);
  
  @override
  Future<User> future(int id) => _userRepository.getUserById(id);
}

and then call load or refresh with the arguments.

context.read<GetUserByIdCubit>().load(1);

or

context.read<GetUserByIdCubit>().refresh(1);

Creating a StreamCubit

StreamCubits are a type of Cubit that can be used to listen to async stream of events. E.g. listening to a stream of data from a websocket.

class NewMessageCubit extends StreamCubit<Message> {
  final MessageRepository _messageRepository;

  GetMessagesCubit(this._messageRepository);
  
  @override
  Stream<Message> dataStream() => _messageRepository.newMessageStream();
}