Combine Bloc

An implementation of the ´BLoC´ (Business Logic Component) with Apple’s Combine framework.

BLoC is a business logic layer abstraction in which you input an Event and it outputs a State. This abstraction contributes to the construction of reactive apps that respects the unidirectional data flow and have a single source of truth. A Bloc from the CombineBloc package is a composite object that has a Subscriber which receives Event and a Publisher of State. A closure is called inside the Bloc everytime a new Event is received by the Subscriber. This closure may emit a new State through the Publisher.

The key points are:

Inputs and outputs are implemented with event-processing operators
Dependencies must be injectable and platform agnostic

This package is inspired by the concept of BLoC proposed by Paolo Soares on DartConf 2018 and by Felix Angelov’s Flutter Bloc State Management Library

Installation

Add this project on your Package.swift

import CombineBloc

let package = Package(
    dependencies: [
        .Package(url: "https://github.com/wjuniorgit/combine-bloc", from: "0.2.0"),
    ],
)

Usage example

This package has three use case examples implemented:

Counter Bloc example

Counter Events

enum CounterEvent: Equatable {
case increment
case decrement
}

Counter State

struct CounterState: Equatable {
let count: Int
}

Counter Bloc

final class CounterBloc: Bloc<CounterEvent, CounterState> {
init() {
    super.init(initialValue: CounterState(count: 0)) {
        event, state, emit in
        switch event {
        case .increment:
            emit(CounterState(count: state.count + 1))
        case .decrement:
            emit(CounterState(count: state.count - 1))
        }
      }
    }
  }

Release History

0.2.0
- The first proper release
0.1.0
- Work in progress