多用户机制:Profile user 桌面图标显示过程

基于android9.x

theme: smartblue

Profile User用户创建成功后，只会在桌面显示寥寥几个应用的图标，而不是所有系统应用；在原生的系统上，profile user创建成功后，会在桌面显示两个profile user应用的图标

场景一：Profile User初次创建成功后，桌面图标显示##

以下以电子邮件应用为例，看下创建Profile user用户后，桌面图标显示的场景

以下调用栈，表示，在Profile User启动后，该应用监听监听了ACTION_BOOT_COMPLETED广播，然后调用setComponentEnabledSetting去启用某些组件

• 调用栈信息

03-07 07:21:06.626  4982  5168 D user    : java.lang.Throwable
03-07 07:21:06.626  4982  5168 D user    :      at android.app.ApplicationPackageManager.setComponentEnabledSetting(ApplicationPackageManager.java:2326)
03-07 07:21:06.626  4982  5168 D user    :      at com.android.email.service.EmailServiceUtils.setComponentStatus(EmailServiceUtils.java:793)
03-07 07:21:06.626  4982  5168 D user    :      at com.android.email.service.EmailServiceUtils.enableExchangeComponent(EmailServiceUtils.java:812)
03-07 07:21:06.626  4982  5168 D user    :      at com.android.email.provider.AccountReconciler.reconcileAccountsInternal(AccountReconciler.java:211)
03-07 07:21:06.626  4982  5168 D user    :      at com.android.email.provider.AccountReconciler.reconcileAccounts(AccountReconciler.java:146)
03-07 07:21:06.626  4982  5168 D user    :      at com.android.email.service.EmailBroadcastProcessorService.reconcileAndStartServices(EmailBroadcastProcessorService.java:371)
03-07 07:21:06.626  4982  5168 D user    :      at com.android.email.service.EmailBroadcastProcessorService.onBootCompleted(EmailBroadcastProcessorService.java:352)
03-07 07:21:06.626  4982  5168 D user    :      at com.android.email.service.EmailBroadcastProcessorService.onHandleIntent(EmailBroadcastProcessorService.java:159)
03-07 07:21:06.626  4982  5168 D user    :      at android.app.IntentService$ServiceHandler.handleMessage(IntentService.java:76)
03-07 07:21:06.626  4982  5168 D user    :      at android.os.Handler.dispatchMessage(Handler.java:106)
03-07 07:21:06.626  4982  5168 D user    :      at android.os.Looper.loop(Looper.java:193)
03-07 07:21:06.626  4982  5168 D user    :      at android.os.HandlerThread.run(HandlerThread.java:65)

• enableExchangeComponent

 public static void enableExchangeComponent(final Context context) {
        if (VendorPolicyLoader.getInstance(context).useAlternateExchangeStrings()) {
            LogUtils.d(LogUtils.TAG, "Enabling alternate EAS authenticator");
            setComponentStatus(context, EasAuthenticatorServiceAlternate.class, true);
            setComponentStatus(context, EasAuthenticatorService.class, false);
        } else {
            LogUtils.d(LogUtils.TAG, "Enabling EAS authenticator");
            setComponentStatus(context, EasAuthenticatorService.class, true);
            setComponentStatus(context,
                    EasAuthenticatorServiceAlternate.class, false);
        }
    }

@Override
public void setComponentEnabledSetting(ComponentName componentName,int newState, int flags) {

    try {
        mPM.setComponentEnabledSetting(componentName, newState, flags, mContext.getUserId());//传递当前应用进程所在的userid，到pms
    } catch (RemoteException e) {
        throw e.rethrowFromSystemServer();
    }
}

从广播发送到桌面去更新桌面图标的流程如下：

流程描述如下：

1. Profile User创建成功后，发送ACTION_BOOT_COMPLETED广播

2. 电子邮件应用，接收ACTION_BOOT_COMPLETED广播，调用PMS#setComponentEnabledSetting去使能相关组件服务

3. PMS处理相关逻辑，使能相关组件服务后，发送ACTION_PACKAGE_CHANGED广播，回调IOnAppsChangeListener的onPacakgeChange方法

4. 因为桌面注册了IOnAppsChangeListener监听，因此能够监听到改pacakgeChange变化，更新对应用户的桌面图标变化

   桌面使用的注册监听的接口

LauncherApps.java
public void registerCallback(Callback callback, Handler handler) {
    synchronized (this) {
        if (callback != null && findCallbackLocked(callback) < 0) {
            boolean addedFirstCallback = mCallbacks.size() == 0;
            addCallbackLocked(callback, handler);
            if (addedFirstCallback) {
                try {
                    mService.addOnAppsChangedListener(mContext.getPackageName(),
                            mAppsChangedListener);
                } catch (RemoteException re) {
                    throw re.rethrowFromSystemServer();
                }
            }
        }
    }
}