RxSwift - Swift 中的响应式编程

Created at: 2015-04-08 05:25:17
Language: Swift
License: MIT

RxSwift 徽标
构建状态 支持的平台:iOS,macOS,tvOS,watchOS和Linux

Rx 是通过接口表示的计算的通用抽象,它允许你广播和订阅流中的值和其他事件。

Observable<Element>
Observable

RxSwift 是 Reactive Extensions 标准的 Swift 专用实现。

RxSwift  Observable 价格不断变化和更新应用程序 UI 的示例

虽然此版本旨在忠于 Rx 的原始精神和命名约定,但该项目还旨在为 Rx API 提供真正的 Swift 优先 API。

可以在 ReactiveX.io 上找到跨平台文档。

与其他 Rx 实现一样,RxSwift 的目的是以对象和一套方法来转换和组合这些异步工作片段,从而轻松地以对象的形式组合异步操作和数据流。

Observable

KVO观察,异步操作,UI事件和其他数据流都在序列抽象下统一。这就是Rx如此简单,优雅和强大的原因。

我来这里是因为我想...

...理解
...安装
  • 将 RxSwift/RxCocoa 与我的应用程序集成。 安装指南
...四处劈砍
...互动
...比较
...了解结构

RxSwift 与它驱动的异步工作一样具有组合性。核心单元是 RxSwift 本身,而其他依赖项可以添加到 UI 工作、测试等。

它由五个独立的组件组成,按以下方式相互依赖:

┌──────────────┐    ┌──────────────┐
│   RxCocoa    ├────▶   RxRelay    │
└───────┬──────┘    └──────┬───────┘
        │                  │        
┌───────▼──────────────────▼───────┐
│             RxSwift              │
└───────▲──────────────────▲───────┘
        │                  │        
┌───────┴──────┐    ┌──────┴───────┐
│    RxTest    │    │  RxBlocking  │
└──────────────┘    └──────────────┘
  • RxSwift: The core of RxSwift, providing the Rx standard as (mostly) defined by ReactiveX. It has no other dependencies.
  • RxCocoa: Provides Cocoa-specific capabilities for general iOS/macOS/watchOS & tvOS app development, such as Shared Sequences, Traits, and much more. It depends on both
    RxSwift
    and
    RxRelay
    .
  • RxRelay: Provides
    PublishRelay
    ,
    BehaviorRelay
    and
    ReplayRelay
    , three simple wrappers around Subjects. It depends on
    RxSwift
    .
  • RxTest and RxBlocking: Provides testing capabilities for Rx-based systems. It depends on
    RxSwift
    .

Usage

Here's an example In Action
Define search for GitHub repositories ...
let searchResults = searchBar.rx.text.orEmpty
    .throttle(.milliseconds(300), scheduler: MainScheduler.instance)
    .distinctUntilChanged()
    .flatMapLatest { query -> Observable<[Repository]> in
        if query.isEmpty {
            return .just([])
        }
        return searchGitHub(query)
            .catchAndReturn([])
    }
    .observe(on: MainScheduler.instance)
... then bind the results to your tableview
searchResults
    .bind(to: tableView.rx.items(cellIdentifier: "Cell")) {
        (index, repository: Repository, cell) in
        cell.textLabel?.text = repository.name
        cell.detailTextLabel?.text = repository.url
    }
    .disposed(by: disposeBag)

Requirements

  • Xcode 12.x
  • Swift 5.x

For Xcode 11 and below, use RxSwift 5.x.

Installation

RxSwift doesn't contain any external dependencies.

These are currently the supported installation options:

Manual

Open Rx.xcworkspace, choose

RxExample
and hit run. This method will build everything and run the sample app

CocoaPods

# Podfile
use_frameworks!

target 'YOUR_TARGET_NAME' do
    pod 'RxSwift', '6.5.0'
    pod 'RxCocoa', '6.5.0'
end

# RxTest and RxBlocking make the most sense in the context of unit/integration tests
target 'YOUR_TESTING_TARGET' do
    pod 'RxBlocking', '6.5.0'
    pod 'RxTest', '6.5.0'
end

Replace

YOUR_TARGET_NAME
and then, in the
Podfile
directory, type:

$ pod install

XCFrameworks

Each release starting with RxSwift 6 includes

*.xcframework
framework binaries.

Simply drag the needed framework binaries to your Frameworks, Libraries, and Embedded Content section under your target's General tab.

Note: If you're using

RxCocoa
, be sure to also drag RxCocoaRuntime.xcframework before importing
RxCocoa
.

XCFrameworks说明

Carthage

Add this to

Cartfile

github "ReactiveX/RxSwift" "6.5.0"
$ carthage update

Carthage as a Static Library

Carthage defaults to building RxSwift as a Dynamic Library.

If you wish to build RxSwift as a Static Library using Carthage you may use the script below to manually modify the framework type before building with Carthage:

carthage update RxSwift --platform iOS --no-build
sed -i -e 's/MACH_O_TYPE = mh_dylib/MACH_O_TYPE = staticlib/g' Carthage/Checkouts/RxSwift/Rx.xcodeproj/project.pbxproj
carthage build RxSwift --platform iOS

Swift Package Manager

Note: There is a critical cross-dependency bug affecting many projects including RxSwift in Swift Package Manager. We've filed a bug (SR-12303) in early 2020 but have no answer yet. Your mileage may vary. A partial workaround can be found here.

Create a

Package.swift
file.

// swift-tools-version:5.0

import PackageDescription

let package = Package(
  name: "RxTestProject",
  dependencies: [
    .package(url: "https://github.com/ReactiveX/RxSwift.git", .exact("6.5.0"))
  ],
  targets: [
    .target(name: "RxTestProject", dependencies: ["RxSwift", "RxCocoa"])
  ]
)
$ swift build

To build or test a module with RxTest dependency, set

TEST=1
.

$ TEST=1 swift test

Manually using git submodules

  • Add RxSwift as a submodule
$ git submodule add git@github.com:ReactiveX/RxSwift.git
  • Drag
    Rx.xcodeproj
    into Project Navigator
  • Go to
    Project > Targets > Build Phases > Link Binary With Libraries
    , click
    +
    and select
    RxSwift
    ,
    RxCocoa
    and
    RxRelay
    targets

References