Settings: Allow disabling private DNS for VPN [2/2]

Allows using the VPN's DNS instead of the set private DNS
Automatically restores the previous set mode

Change-Id: Ib7d91bf151ed593648357c1d7e4013d309e2d927

src/com/android/settings/network/PrivateDnsPreferenceController.java

@@ -58,6 +58,7 @@ import java.util.List;
 public class PrivateDnsPreferenceController extends BasePreferenceController
         implements PreferenceControllerMixin, LifecycleObserver, OnStart, OnStop {
     private static final String KEY_PRIVATE_DNS_SETTINGS = "private_dns_settings";
+    private static final String KEY_ENFORCE_VPN_SETTINGS = "vpn_enforce_dns";
 
     private static final Uri[] SETTINGS_URIS = new Uri[]{
         Settings.Global.getUriFor(PRIVATE_DNS_MODE),
@@ -82,6 +83,7 @@ public class PrivateDnsPreferenceController extends BasePreferenceController
     private final ConnectivityManager mConnectivityManager;
     private LinkProperties mLatestLinkProperties;
     private Preference mPreference;
+    private Preference mEnforcePreference;
 
     public PrivateDnsPreferenceController(Context context) {
         super(context, KEY_PRIVATE_DNS_SETTINGS);
@@ -110,6 +112,7 @@ public class PrivateDnsPreferenceController extends BasePreferenceController
         super.displayPreference(screen);
 
         mPreference = screen.findPreference(getPreferenceKey());
+        mEnforcePreference = screen.findPreference(KEY_ENFORCE_VPN_SETTINGS);
     }
 
     @Override
@@ -201,7 +204,11 @@ public class PrivateDnsPreferenceController extends BasePreferenceController
     @Override
     public void updateState(Preference preference) {
         super.updateState(preference);
-        preference.setEnabled(!isManagedByAdmin());
+        final boolean isManaged = isManagedByAdmin();
+        preference.setEnabled(!isManaged);
+        if (mEnforcePreference == null) return;
+        final int mode = ConnectivitySettingsManager.getPrivateDnsMode(mContext);
+        mEnforcePreference.setEnabled(!isManaged && mode != PRIVATE_DNS_MODE_OFF);
     }
 
     private boolean isManagedByAdmin() {

src/com/android/settings/network/PrivateDnsSettings.java

@@ -0,0 +1,78 @@
+/*
+ * Copyright (C) 2023 Yet Another AOSP Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.android.settings.network;
+
+import android.app.settings.SettingsEnums;
+import android.content.Context;
+
+import com.android.settings.R;
+import com.android.settings.dashboard.DashboardFragment;
+import com.android.settings.search.BaseSearchIndexProvider;
+import com.android.settingslib.core.AbstractPreferenceController;
+import com.android.settingslib.core.lifecycle.Lifecycle;
+import com.android.settingslib.search.SearchIndexable;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Adaptive connectivity is a feature which automatically manages network connections.
+ */
+@SearchIndexable
+public class PrivateDnsSettings extends DashboardFragment {
+
+    private static final String TAG = "PrivateDnsSettings";
+
+    @Override
+    public int getMetricsCategory() {
+        return SettingsEnums.SETTINGS_NETWORK_CATEGORY;
+    }
+
+    @Override
+    protected String getLogTag() {
+        return TAG;
+    }
+
+    @Override
+    protected int getPreferenceScreenResId() {
+        return R.xml.private_dns_settings;
+    }
+
+    @Override
+    protected List<AbstractPreferenceController> createPreferenceControllers(Context context) {
+        return buildPreferenceControllers(context, getSettingsLifecycle());
+    }
+
+    private static List<AbstractPreferenceController> buildPreferenceControllers(
+            Context context, Lifecycle lifecycle) {
+        final PrivateDnsPreferenceController privateDnsPreferenceController =
+                new PrivateDnsPreferenceController(context);
+        if (lifecycle != null) {
+            lifecycle.addObserver(privateDnsPreferenceController);
+        }
+        final List<AbstractPreferenceController> controllers = new ArrayList<>();
+        controllers.add(privateDnsPreferenceController);
+        return controllers;
+    }
+
+    public static final BaseSearchIndexProvider SEARCH_INDEX_DATA_PROVIDER =
+            new BaseSearchIndexProvider(R.xml.private_dns_settings) {
+                @Override
+                public List<AbstractPreferenceController> createPreferenceControllers(Context context) {
+                    return buildPreferenceControllers(context, null);
+                }
+            };
+}