Lifecycle Component

2018-05-19 14:11:27   2  举报

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Android Lifecycle的UML图，附带一些源码截图和注释自己边学习边画的，大概理了一下Lifecycle感知生命周期的原理红色*号的是关键方法蓝色背景是Lifecycle相关的类黄色背景是Lifecycle相关接口有错误的地方欢迎指出，一起学习

Android Lifecycle

作者其他创作

大纲/内容

android.support.v4.app.Fragment

performCreate():voidperformCreateView():ViewperformActivityCreated():voidperformStart():voidperformResume():voidperformPause():voidperformStop():voidperformDestory():void

mLifecycleRegistry : LifecycleRegistry

1、SupportActivity在onCreate的时候，给自己加了个ReportFragment用来向LifeCycleRegister发送生命周期状态

Lifecycling

getCallback():GenericLifecycleObserver

ReprotFragment通过SupportActivity的mLifecycleRegistry来发送生命周期状态变化

ReflectiveGenericLifecycleObserver

mInfo : CallbackInfo //LifecycleObserver的信息，主要是检查有没有用OnLifecycleEvent注解的方法mWrapped:Object //这个就是你自定义的LifecycleObserver

android.Fragment

内部静态类

实现

LifecycleRegistry

backwardPass( LifecycleOwner ):void （调用ObserverWithState.dispatchEvent() ）forwardPass( LifecycleOwner ):voidhandleLifecycleEvent( Lifecycle.Event ):void（最终由上面两个函数实现）addObserver( LifecycleObserver ):void

3、LifecycleRegistry.handleLifecycleEvent调用ObserverWithState.dispatchEvent

abstract Lifecycle

Event（enum）

ON_CREATEON_STARTON_RESUMEON_PAUSEON_STOPON_DESTROYON_ANY

ReportFragment

+ dispatchCreate(ActivityInitializationListener):void+ dispatchStart(ActivityInitializationListener):void+ dispatchResume(ActivityInitializationListener):void+ dispatch(LifeCycle.Event event)

4、ObserverWithState.dispatchEvent调用ReflectiveGenericLifecycleObserver. onStateChanged

内部类

GenericLifecycleObserver

LifecycleObserver

Lifecycle是怎么让观察者知道Activity/Fragment的生命周期状态的？

ObserverWithState

mLifecycleObserver: GenericLifecycleObserver

继承

2、ReprotFragment在每个生命周期方法中调用dispatch方法，通过SupportActivity的lifecycle发送生命周期状态

LifeCycleOnwer

- Lifecycle getLifecycle();

SupportActivity