这里总结下我研究这个需求，想出的两种解决方案。

第一种方法最简单暴力只要修改apk的AndroidManifest直接上源码

这里就加了一句android:priority=”2”，这样在开机和按HOME键时候系统intent判断到category.HOME属性后如果有多个此属性apk，则会进入ResolverActivity让用户选择。当你定义了此优先级它其他未定义的都默认为0，所以优先进入了你的activity。

第二种方法需要修改framework源码来强制进入你的launcher

首先ActivityManagerService.java中

boolean startHomeActivityLocked(int userId) {

if (mHeadless) {

// Added because none of the other calls to ensureBootCompleted seem to fire

// when running headless.

ensureBootCompleted();

return false;

}

if (mFactoryTest == SystemServer.FACTORY_TEST_LOW_LEVEL

&& mTopAction == null) {

// We are running in factory test mode, but unable to find

// the factory test app, so just sit around displaying the

// error message and don't try to start anything.

return false;

}

Intent intent = getHomeIntent();

ActivityInfo aInfo =

resolveActivityInfo(intent, STOCK_PM_FLAGS, userId);

if (aInfo != null) {

//add wwd start

PackageManager pm = mContext.getPackageManager();

Intent newintent = new Intent(Intent.ACTION_MAIN);

newintent.addCategory(Intent.CATEGORY_HOME);

List resolveInfoList = pm.queryIntentActivities(newintent, 0);

//判断带有Intent.CATEGORY_HOME标签的所有activity中如果有你指定的activity则替换

if(resolveInfoList != null){

int size = resolveInfoList.size();

for(int i = 0; i < size; i++){

ResolveInfo rInfo = resolveInfoList.get(i);

if(rInfo.activityInfo.name.equals("com.android.launcher3.Launcher")){

aInfo = rInfo.activityInfo;

}

}

}

//add wwd stop

intent.setComponent(new ComponentName(

aInfo.applicationInfo.packageName, aInfo.name));

// Don't do this if the home app is currently being

// instrumented.

aInfo = new ActivityInfo(aInfo);

aInfo.applicationInfo = getAppInfoForUser(aInfo.applicationInfo, userId);

ProcessRecord app = getProcessRecordLocked(aInfo.processName,

aInfo.applicationInfo.uid, true);

if (app == null || app.instrumentationClass == null) {

intent.setFlags(intent.getFlags() | Intent.FLAG_ACTIVITY_NEW_TASK);

//这里启动你已替换过的activity

mStackSupervisor.startHomeActivity(intent, aInfo);

}

}

return true;

}

这样就把开机homeactivity替换成你想要启动的luncher了。

下面在修改按home键强制退回的launcher

PhoneWindowManager.java

public void init(Context context, IWindowManager windowManager,

WindowManagerFuncs windowManagerFuncs) {

......

mHomeIntent = new Intent(Intent.ACTION_MAIN, null);

mHomeIntent.addCategory(Intent.CATEGORY_HOME);

//add wwd start

ComponentName mHomecom = new ComponentName("com.android.launcher3", "com.android.launcher3.Launcher");

mHomeIntent.setComponent(mHomecom);

//add wwd stop

mHomeIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK

| Intent.FLAG_ACTIVITY_RESET_TASK_IF_NEEDED);

......

}

这里添加以上两句让home强制跳转指定launcher就好了。