在 ActivityManagerService 里启动 Launcher
Lollipop/frameworks/base/services/core/java/com/android/server/am/ActivityManagerService.java
Intent getHomeIntent() {
Intent intent = new Intent(mTopAction, mTopData != null ? Uri.parse(mTopData) : null);
intent.setComponent(mTopComponent);
if (mFactoryTest != FactoryTest.FACTORY_TEST_LOW_LEVEL) {
intent.addCategory(Intent.CATEGORY_HOME);
}
return intent;
}
boolean startHomeActivityLocked(int userId, String reason) {
// ...
Intent intent = getHomeIntent();
// ...
}
