CombineFeedback 使用教程

CombineFeedback 使用教程

CombineFeedbackUnidirectional reactive architecture using new Apple Combine framework https://developer.apple.com/documentation/combine项目地址:https://gitcode.com/gh_mirrors/co/CombineFeedback

项目介绍

CombineFeedback 是一个基于 Apple 的 Combine 框架实现的无向反应式架构项目。它旨在简化 iOS 应用的状态管理和反应式编程，特别是当你担心过度复杂的代码库时。CombineFeedback 的核心思想是通过单一数据源（State）、事件（Event）、还原器（Reducer）和反馈（Feedback）来定义系统的状态变化。此外，该库还借鉴了 Composable Architecture（TCA）的理念，鼓励代码的可组合性，使得模块化更加容易。

项目快速启动

安装

首先，确保你已经安装了 Xcode 和 Swift 工具链。然后，你可以通过 Swift Package Manager 安装 CombineFeedback。在你的 Package.swift 文件中添加以下依赖：

dependencies: [
    .package(url: "https://github.com/sergdort/CombineFeedback.git", from: "0.1.0")
]

基本使用

以下是一个简单的示例，展示如何使用 CombineFeedback 创建一个计数器应用：

import Combine
import CombineFeedback
import SwiftUI

struct CounterState {
    var count: Int = 0
}

enum CounterEvent {
    case increment
    case decrement
}

let counterReducer = Reducer<CounterState, CounterEvent> { state, event in
    switch event {
    case .increment:
        state.count += 1
    case .decrement:
        state.count -= 1
    }
}

let counterFeedback = Feedback<CounterState, CounterEvent> { state in
    return Empty().eraseToAnyPublisher()
}

let store = Store(
    initial: CounterState(),
    reducer: counterReducer,
    feedback: counterFeedback
)

struct CounterView: View {
    let store: Store<CounterState, CounterEvent>

    var body: some View {
        WithViewStore(store) { viewStore in
            VStack {
                Text("Count: \(viewStore.count)")
                Button("Increment") {
                    viewStore.send(.increment)
                }
                Button("Decrement") {
                    viewStore.send(.decrement)
                }
            }
        }
    }
}

@main
struct CounterApp: App {
    var body: some Scene {
        WindowGroup {
            CounterView(store: store)
        }
    }
}

应用案例和最佳实践

无限滚动列表

CombineFeedback 可以优雅地处理无限滚动列表。当用户滚动到列表底部时，它会自动触发加载更多数据的事件，而这一切都无需直接修改 State。

struct InfiniteListState {
    var items: [Item] = []
    var nextPage: Int? = 1
}

enum InfiniteListEvent {
    case loadMore
    case didLoad(items: [Item])
    case didFail(error: Error)
}

let infiniteListReducer = Reducer<InfiniteListState, InfiniteListEvent> { state, event in
    switch event {
    case .loadMore:
        state.nextPage = state.nextPage.map { $0 + 1 }
    case .didLoad(let items):
        state.items.append(contentsOf: items)
        state.nextPage = nil
    case .didFail:
        state.nextPage = nil
    }
}

let infiniteListFeedback = Feedback<InfiniteListState, InfiniteListEvent> { state in
    guard let nextPage = state.nextPage else { return Empty().eraseToAnyPublisher() }
    return URLSession.shared.fetchItems(page: nextPage)
        .map(InfiniteListEvent.didLoad)
        .replaceError(with: InfiniteListEvent.didFail(error: NSError()))
        .receive(on: DispatchQueue.main)
        .eraseToAnyPublisher()
}

典型生态项目

SwiftUI 集成

CombineFeedback 与 SwiftUI 无缝对接，提供方便的渲染上下文（ViewContext）以绑定 State 和事件。

struct MyView: View {
    let store: Store<MyState, MyEvent>

    var body: some View {
        WithViewStore(store) { viewStore in
            VStack {
                Text("Current State: \(viewStore.stateDescription)")
                Button("Trigger Event") {
                    view

CombineFeedbackUnidirectional reactive architecture using new Apple Combine framework https://developer.apple.com/documentation/combine项目地址:https://gitcode.com/gh_mirrors/co/CombineFeedback