在 Android 11 中，系统对应用的权限管理进行了进一步的细化和增强。关于默认给予应用通知权限这一特性，通常情况下，
应用在安装后并不会自动获得所有的权限，包括通知权限。应用必须明确请求所需的权限，并且用户需要在权限请求对话框中授权。

//检查是否具有通知使用权，都是在系统中的secure 数据库,利用命令adb shell settings list secure可以查看
C:\Users\xx>adb shell settings list secure可以查看
accessibility_display_inversion_enabled=null
accessibility_display_magnification_enabled=0
accessibility_display_magnification_scale=2.0
accessibility_enabled=0
adaptive_sleep=null
android_id=6bcce84ef38428a
autofill_service=
aware_enabled=0
aware_lock_enabled=0
backup_enabled=0
backup_transport=com.android.localtransport/.LocalTransport
bluetooth_name=rk3566
charging_sounds_enabled=0
charging_vibration_enabled=1
clock_seconds=null
default_input_method=com.android.inputmethod.latin/.LatinIME
double_tap_to_wake=1
doze_pulse_on_double_tap=null
doze_tap_gesture=null
enabled_input_methods=com.android.inputmethod.latin/.LatinIME
enabled_notification_assistant=android.ext.services/android.ext.services.notification.Assistant
enabled_notification_policy_access_packages=com.android.demo:com.android.camera2//这里
high_priority=null
刷机第一次开机NotificationManagerService开启流程：

loadPolicyFile()->allowDefaultApprovedServices(USER_SYSTEM)
->allowDndPackage(...)
->getBinderService().setNotificationPolicyAccessGranted(packageName, true);
    protected void allowDefaultApprovedServices(int userId) {
        ArraySet<ComponentName> defaultListeners = mListeners.getDefaultComponents();
        for (int i = 0; i < defaultListeners.size(); i++) {
            ComponentName cn = defaultListeners.valueAt(i);
            allowNotificationListener(userId, cn);
        ArraySet<String> defaultDnds = mConditionProviders.getDefaultPackages();
        //add text 添加需要开机通知权限的包名
        defaultDnds.add("com.xx.xx");
        //add text
        for (int i = 0; i < defaultDnds.size(); i++) {
            allowDndPackage(defaultDnds.valueAt(i));
        setDefaultAssistantForUser(userId);
    private void allowDndPackage(String packageName) {
        try {
            getBinderService().setNotificationPolicyAccessGranted(packageName, true);
        } catch (RemoteException e) {
            e.printStackTrace();
方案二：（试过不太能行）

./frameworks/base/core/res/res/values/config.xml

通过在 config.xml 或任何原始设备制造商 (OEM) 叠加层中将某个应用的软件包名称添加到 config_defaultListenerAccessPackages，

可以将此应用指定为默认通知监听器。默认通知监听器有权访问所有传入通知，

但用户可以在“设置”应用中的“通知使用权”设置中关闭对通知的使用权。
通知使用权和通知监听器政策  | Android Open Source Project (google.cn)
默认授予通知监听器访问权限,多个用冒号分隔的包名 如：com.xx.xx:com.android.camera2
<!-- Colon separated list of package names that should be granted Notification Listener access -->
<string name="config_defaultListenerAccessPackages" translatable="false">com.xxx.xxx</string>
./frameworks/base/services/core/java/com/android/server/notification/NotificationManagerService.java
        @Override
        protected void loadDefaultsFromConfig() {
            String defaultListenerAccess = mContext.getResources().getString(
                    R.string.config_defaultListenerAccessPackages);
            if (defaultListenerAccess != null) {
                //private static final String ENABLED_SERVICES_SEPARATOR = ":";
                String[] listeners =
                        defaultListenerAccess.split(ManagedServices.ENABLED_SERVICES_SEPARATOR);//用":"分割成数组
                for (int i = 0; i < listeners.length; i++) {
                    if (TextUtils.isEmpty(listeners[i])) {
                        continue;
                    ArraySet<ComponentName> approvedListeners =
                            this.queryPackageForServices(listeners[i],
                                    MATCH_DIRECT_BOOT_AWARE
                                            | MATCH_DIRECT_BOOT_UNAWARE, USER_SYSTEM);
                    for (int k = 0; k < approvedListeners.size(); k++) {
                        ComponentName cn = approvedListeners.valueAt(k);
                        addDefaultComponentOrPackage(cn.flattenToString());
方案三：给予某个app通知权限（app启动时）
final NotificationManager mgr = context.getSystemService(NotificationManager.class);
mgr.setNotificationPolicyAccessGranted(pkg, access);
--- a/sprd/frameworks/base/core/java/android/app/ActivityThread.java
+++ b/sprd/frameworks/base/core/java/android/app/ActivityThread.java
@@ -242,6 +242,7 @@ import java.util.concurrent.Executor;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.function.Consumer;
 import android.app.LinkTurboApp;
+import android.app.NotificationManager;
public final class ActivityThread extends ClientTransactionHandler {
//applicationContext.getSystemService(WindowManager.class).getDefaultDisplay();
@Override
    public Activity handleLaunchActivity(ActivityClientRecord r,
            PendingTransactionActions pendingActions, Intent customIntent) {
         unscheduleGcIdler();
         mSomeActivitiesChanged = true;
         //add text
        //uid 权限问题 报异常 java.lang.SecurityException   
        }catch(Exception e)  {
           final NotificationManager mgr = mInitialApplication.getApplicationContext().getSystemService(NotificationManager.class);
           mgr.setNotificationPolicyAccessGranted("com.xx.xx", true);      
    //add text
        if (r.profilerInfo != null) {
            mProfiler.setProfiler(r.profilerInfo);
            mProfiler.startProfiling();
方案四：在某个启动的系统服务类，调用setNotificationPolicyAccessGranted(...)
frameworks/base/services/core/java/com/android/server/policy/PhoneWindowManager.java
//系统启动,当主要服务启动完毕后,调用systemReady()来启动其它的功能！这里是每次开机必走的！
 @Override
 public void systemReady() {
     // In normal flow, systemReady is called before other system services are ready.
     // So it is better not to bind keyguard here.
     mKeyguardDelegate.onSystemReady();
     // add text start
      NotificationManager mgr = mContext.getSystemService(NotificationManager.class);
      mgr.setNotificationPolicyAccessGranted("com.xx.xx", true); 
      //ComponentName componentName = new ComponentName("com.xxx.xx","xx.xx.xx.xx");
      //mgr.setNotificationListenerAccessGranted(componentName, true);
     // add text end