1.概述

在12.0的进行系统定制化开发中，在内置一些app需要收到开机广播以后然后做一些相关的操作的功能的时候，发现开机广播要好久能收到，要么就收不到开机广播，所以这就需要了解开机广播在哪里发送，然后自定义开机广播来接收自定义开机广播然后开发一些功能

2.framework添加自定义开机广播的核心代码

    /frameworks/base/core/java/android/app/ActivityThread.java/frameworks/base/services/core/java/com/android/server/wm/ActivityTaskManagerService.java/frameworks/base/services/core/java/com/android/server/wm/ActivityStackSupervisor.java/frameworks/base/services/core/java/com/android/server/wm/WindowManagerService.java/frameworks/base/services/core/java/com/android/server/am/UserController.java

3.framework添加自定义开机广播的功能分析以及实现
  3.1 ActivityThread.java关于开机的相关代码

    public void handleResumeActivity(IBinder token, Boolean finalStateRequest, Boolean isForward,String reason) {// If we are getting ready to gc after going to the background, well// we are back ac