Do not allow draw on top for App notification settings

Fixes: 119115683
Test: manual
Change-Id: Ib7b878a23b4a99171c58b5de992fb87feca8a28a

src/com/android/settings/notification/AppNotificationSettings.java

@@ -16,6 +16,8 @@
 
 package com.android.settings.notification;
 
+import static android.view.WindowManager.LayoutParams.SYSTEM_FLAG_HIDE_NON_SYSTEM_OVERLAY_WINDOWS;
+
 import android.app.NotificationChannel;
 import android.app.NotificationChannelGroup;
 import android.app.settings.SettingsEnums;
@@ -24,6 +26,8 @@ import android.os.AsyncTask;
 import android.os.Bundle;
 import android.text.TextUtils;
 import android.util.Log;
+import android.view.Window;
+import android.view.WindowManager;
 
 import androidx.preference.Preference;
 import androidx.preference.PreferenceCategory;
@@ -33,7 +37,6 @@ import androidx.preference.SwitchPreference;
 
 import com.android.internal.widget.LockPatternUtils;
 import com.android.settings.R;
-import com.android.settings.widget.MasterCheckBoxPreference;
 import com.android.settingslib.RestrictedSwitchPreference;
 import com.android.settingslib.core.AbstractPreferenceController;
 
@@ -85,6 +88,8 @@ public class AppNotificationSettings extends NotificationSettingsBase {
     public void onResume() {
         super.onResume();
 
+        getActivity().getWindow().addSystemFlags(SYSTEM_FLAG_HIDE_NON_SYSTEM_OVERLAY_WINDOWS);
+
         if (mUid < 0 || TextUtils.isEmpty(mPkg) || mPkgInfo == null) {
             Log.w(TAG, "Missing package or uid or packageinfo");
             finish();
@@ -118,6 +123,15 @@ public class AppNotificationSettings extends NotificationSettingsBase {
         updatePreferenceStates();
     }
 
+    @Override
+    public void onPause() {
+        super.onPause();
+        final Window window = getActivity().getWindow();
+        final WindowManager.LayoutParams attrs = window.getAttributes();
+        attrs.privateFlags &= ~SYSTEM_FLAG_HIDE_NON_SYSTEM_OVERLAY_WINDOWS;
+        window.setAttributes(attrs);
+    }
+
     @Override
     protected String getLogTag() {
         return TAG;