從功能需求、設(shè)計(jì)模式、最佳實(shí)踐出發(fā)考慮

MVP模式

數(shù)據(jù)、顯示、控制解耦，mosby，作者blog1，blog2

依賴注入

• 普通數(shù)據(jù)注入，Dagger
• View注入ButterKnife。

數(shù)據(jù)存儲(chǔ)

• squidb，基于注解，編譯期生成DAO類，model類是編譯期生成的，而不是定義表結(jié)構(gòu)的類，對(duì)復(fù)雜SQL語(yǔ)句的支持非常好
• DBFlow，基于注解，編譯期生成DAO類，對(duì)關(guān)系的支持很好
• ActiveAndroid，基于注解，運(yùn)行時(shí)轉(zhuǎn)換
• greenDAO，編譯期生成輔助代碼
• StorIO，與rx集成，響應(yīng)式DBHelper框架

網(wǎng)絡(luò)連接處理

• Retrofit，使用動(dòng)態(tài)代理將java接口轉(zhuǎn)化為REST API
• OkHttp，優(yōu)化的HTTP client（共享連接，連接池，透明壓縮，緩存，重試等），支持web socket協(xié)議

異步處理

• 響應(yīng)式編程（rx，在java7中使用lambda語(yǔ)法：retrolambda），消息的發(fā)出者和響應(yīng)的接收者在同一模塊內(nèi)，局部性、單對(duì)單
• 事件處理（EventBus，Otto），全局性事件、一對(duì)多比較合適

測(cè)試

• 單元測(cè)試（我的印象筆記，Robolectric，使得Android代碼能夠在PC的JVM上運(yùn)行測(cè)試，加快速度）
  • 對(duì)rx的單元測(cè)試，非官方RxAssertions，官方TestSubscriber
  • AndroidTDD
• 集成測(cè)試（我的印象筆記，Espresso）

持續(xù)集成

• jenkins-ci，整合代碼托管工具，commit、merge request自動(dòng)觸發(fā)構(gòu)建

工具

• 圖片加載
  • Fresco，多來(lái)源加載、緩存、內(nèi)存管理（存放在安卓非堆特殊內(nèi)存區(qū)域）、支持多種格式、多種功能（圓角）
  • Glide，多來(lái)源加載、緩存、Object pool內(nèi)存優(yōu)化、Context生命周期加載優(yōu)化、ListView、RecyclerView等加載優(yōu)化
  • Picasso，使用堆內(nèi)存，格式稍少
• 模塊熱加載
  • dynamic-load-apk，通過(guò)代理實(shí)現(xiàn)啟動(dòng)、顯示、執(zhí)行安裝時(shí)未定義的Activity，Service，實(shí)現(xiàn)模塊熱加載
• 錯(cuò)誤統(tǒng)計(jì)
  • fabric，提供crash統(tǒng)計(jì)、以及twitter集成
• 調(diào)試
  • XLog，函數(shù)調(diào)用追蹤，log出參數(shù)、返回值、線程、執(zhí)行時(shí)間，支持方法、類的注解；
  • Fresco，chrome查看log，view heriachy，shared pref，db等；
  • LeakCanary，memory leak檢測(cè)工具；
• 時(shí)間
  • ThreeTenBP，JSR310的java 8以前的兼容實(shí)現(xiàn)，比安卓的Date類等強(qiáng)大無(wú)數(shù)倍；
  • ThreeTenABP，安卓的一個(gè)包裝，init過(guò)程性能更好；
• 導(dǎo)航
  • FragmentArgs，F(xiàn)ragment啟動(dòng)時(shí)通過(guò)Argument傳遞參數(shù)
  • Dart，Activity之間通過(guò)Intent傳遞Extra參數(shù)
  • Pocket Knife，Activity的Extra傳遞參數(shù)，SavedInstance做狀態(tài)保存/恢復(fù)
  • Aftermath，A simple, annotation-based Android library for generating onActivityForResult handlers.
• 動(dòng)效
  • rebound，通過(guò)Android系統(tǒng)的property transition，加上各種變換函數(shù)，實(shí)現(xiàn)模擬物理的動(dòng)效；
• 設(shè)計(jì)
  • sketch
  • zeplin

Develop maintainable apps

• Libraries
  選擇第三方庫(kù)時(shí)的考慮
  • Documentation: 文檔是否全面
  • Repository Check-ins(Stability): 穩(wěn)定性、是否保持維護(hù)
  • Fulfils a Need: 滿足項(xiàng)目需求
• Domain design
  • Keep code simple: OO，一個(gè)類只負(fù)責(zé)一件事
  • Use MVC/MVP/MVVM Pattern
  • Functional Test
  • Use the tools: IDE的重構(gòu)工具很強(qiáng)大
• Code quality
  • Readability matters
  • 工具
    • CheckStyle
    • Lint
    • Findbugs
    • PMD
  • Refactor Gradually
• Testing
  • Unit test: Every single line of code that you write should be tested. Peroid. -- Robert Martin
  • Junit(...) + Mockito
  • Continuous Integration
  • Code coverage

Android Clean Architecture

分層結(jié)構(gòu)

http://wiki.jikexueyuan.com/project/notes/images/clean_architecture1.png" alt="clean_architecture1.png" />

• Entities: These are the business objects of the application.
• Use Cases: These use cases orchestrate the flow of data to and from the entities. Are also called Interactors.
• Interface Adapters: This set of adapters convert data from the format most convenient for the use cases and entities. Presenters and Controllers belong here.
• Frameworks and Drivers: This is where all the details go: UI, tools, frameworks, etc.
• Dependency Rule: source code dependencies can only point inwards and nothing in an inner circle can know anything at all about something in an outer circle.

安卓項(xiàng)目層次結(jié)構(gòu)示例

http://wiki.jikexueyuan.com/project/notes/images/clean_architecture_android.png" alt="clean_architecture_android.png" />

使用Rx后的層次結(jié)構(gòu)示例

http://wiki.jikexueyuan.com/project/notes/images/clean_architecture_evolution.png" alt="clean_architecture_evolution.png" />

• Presentation layer: UI tests with Espresso 2 and Android Instrumentation.
• Presenter && View test: 針對(duì)接口進(jìn)行單元測(cè)試；對(duì)UI簡(jiǎn)單交互結(jié)果邏輯的測(cè)試（如：Activity跳轉(zhuǎn)，F(xiàn)ragment切換，相關(guān)接口調(diào)用）；
• Domain layer: JUnit + Mockito since it is a regular Java module.
• Data layer: Migrated test battery to use Robolectric 3 + JUnit + Mockito.

代碼組織（包組織）

• Package by layer
• Package by feature
  • Higher Modularity
  • Easier Code Navigation
  • Minimizes Scope

Flux Architecture

• 結(jié)構(gòu)圖
  http://wiki.jikexueyuan.com/project/notes/images/flux-graph-simple.png" alt="flux-graph-simple.png" />
  • View: Application interface. It create actions in response to user interactions. Activity or Fragment
  • Dispatcher: Central hub through which pass all actions and whose responsibility is to make them arrive to every Store. An event bus.
  • Store: Maintain the state for a particular application domain. They respond to actions according to current state, execute business logic and emit a change event when they are done. This event is used by the view to update its interface. Simple POJOs with two main attributes: Type: a String identifying the type of event; Data: a Map with the payload for this action.
  • More about Stores
    • Stores contain the status of the application and its business logic.
    • Stores react to Actions emitted by the Dispatcher, execute business logic and emit a change event as result.
    • ...

RxFlux

http://wiki.jikexueyuan.com/project/notes/images/rxflux_arch.png" alt="rxflux_arch.png" />

What is all this Clean Architecture jibber-jabber about?

基礎(chǔ)

• SOLID
  • Single Responsiblity
  • Open/Closed
  • Liskov Substitution
  • Interface Segregation
  • Dependency Inversion
• Abstraction
  • 面向接口編程
  • 高內(nèi)聚，低耦合
    • 內(nèi)聚：?jiǎn)我荒K內(nèi)，各個(gè)部分之間的關(guān)系
    • 耦合：各個(gè)模塊之間的關(guān)系
• Vertical slicing
  • Horizontal slicing：傳統(tǒng)方式，從服務(wù)提供方分包，例如DB, Network, ui...
  • Vertical slicing：源自敏捷，根據(jù)功能（use case）進(jìn)行分包，而將與該功能相關(guān)的db, network, ui等部分放到同一個(gè)模塊中