Allows for system navigation settings to be added dynamically.

This allows for controller-backed preferences to be added or
overridden via xml.

Similarly, if the controllers cause all of the preferences for
2 or 3 button nav to be unavailable, we hide the settings button.

Bug: 324036308
Test: Manual and unit tests
Flag: NA
Change-Id: I2371f3173076172489966728ac69c8767570cd56
Merged-In: I2371f3173076172489966728ac69c8767570cd56

res/values/strings.xml

@@ -10478,7 +10478,7 @@
     <string name="back_sensitivity_dialog_title">Back Sensitivity</string>
 
     <!-- Title for the screen to show all the gesture navigation settings [CHAR LIMIT=80] -->
-    <string name="gesture_settings_activity_title">Gesture Navigation Sensitivity</string>
+    <string name="gesture_settings_activity_title">Gesture Navigation</string>
 
     <!-- Title for the screen to show all the 2- and 3-button navigation settings. [CHAR LIMIT=80] -->
     <string name="button_navigation_settings_activity_title">Button navigation</string>

src/com/android/settings/core/PreferenceControllerListHelper.java

@@ -27,6 +27,8 @@ import android.text.TextUtils;
 import android.util.Log;
 
 import androidx.annotation.NonNull;
+import androidx.preference.PreferenceManager;
+import androidx.preference.PreferenceScreen;
 
 import com.android.settings.core.PreferenceXmlParserUtils.MetadataFlag;
 import com.android.settingslib.core.AbstractPreferenceController;
@@ -93,6 +95,25 @@ public class PreferenceControllerListHelper {
         return controllers;
     }
 
+    /**
+     * Checks if the given PreferenceScreen will be empty due to all preferences being unavailable.
+     *
+     * @param xmlResId resource id of the PreferenceScreen to check
+     * @return {@code true} if none of the preferences in the given screen will appear
+     */
+    public static boolean areAllPreferencesUnavailable(@NonNull Context context,
+            @NonNull PreferenceManager preferenceManager, @XmlRes int xmlResId) {
+        PreferenceScreen screen = preferenceManager.inflateFromResource(context, xmlResId,
+                /* rootPreferences= */ null);
+        List<BasePreferenceController> preferenceControllers =
+                getPreferenceControllersFromXml(context, xmlResId);
+        if (screen.getPreferenceCount() != preferenceControllers.size()) {
+            // There are some preferences without controllers, which will show regardless.
+            return false;
+        }
+        return preferenceControllers.stream().noneMatch(BasePreferenceController::isAvailable);
+    }
+
     /**
      * Return a sub list of {@link AbstractPreferenceController} to only contain controller that
      * doesn't exist in filter.

src/com/android/settings/gestures/SystemNavigationGestureSettings.java

@@ -43,6 +43,8 @@ import androidx.preference.PreferenceScreen;
 
 import com.android.settings.R;
 import com.android.settings.accessibility.AccessibilityGestureNavigationTutorial;
+import com.android.settings.core.BasePreferenceController;
+import com.android.settings.core.PreferenceControllerListHelper;
 import com.android.settings.core.SubSettingLauncher;
 import com.android.settings.dashboard.suggestions.SuggestionFeatureProvider;
 import com.android.settings.overlay.FeatureFactory;
@@ -147,14 +149,20 @@ public class SystemNavigationGestureSettings extends RadioButtonPickerFragment i
         final PreferenceScreen screen = getPreferenceScreen();
         screen.removeAll();
         screen.addPreference(mVideoPreference);
+        addPreferencesFromResource(getPreferenceScreenResId());
+        final List<BasePreferenceController> preferenceControllers = PreferenceControllerListHelper
+                .getPreferenceControllersFromXml(getContext(), getPreferenceScreenResId());
+        preferenceControllers.forEach(controller -> {
+            controller.updateState(findPreference(controller.getPreferenceKey()));
+            controller.displayPreference(screen);
+        });
 
         final List<? extends CandidateInfo> candidateList = getCandidates();
         if (candidateList == null) {
             return;
         }
         for (CandidateInfo info : candidateList) {
-            SelectorWithWidgetPreference pref =
+            SelectorWithWidgetPreference pref = new SelectorWithWidgetPreference(getPrefContext());
-                    new SelectorWithWidgetPreference(getPrefContext());
             bindPreference(pref, info.getKey(), info, defaultKey);
             bindPreferenceExtra(pref, info.getKey(), info, defaultKey, systemDefaultKey);
             screen.addPreference(pref);
@@ -176,8 +184,11 @@ public class SystemNavigationGestureSettings extends RadioButtonPickerFragment i
                     GestureNavigationSettingsFragment.GESTURE_NAVIGATION_SETTINGS)));
         }
 
-        if (KEY_SYSTEM_NAV_2BUTTONS.equals(info.getKey()) || KEY_SYSTEM_NAV_3BUTTONS.equals(
+        if ((KEY_SYSTEM_NAV_2BUTTONS.equals(info.getKey())
-                info.getKey())) {
+                || KEY_SYSTEM_NAV_3BUTTONS.equals(info.getKey()))
+                // Don't add the settings button if that page will be blank.
+                && !PreferenceControllerListHelper.areAllPreferencesUnavailable(
+                        getContext(), getPreferenceManager(), R.xml.button_navigation_settings)) {
             pref.setExtraWidgetOnClickListener((v) ->
                     new SubSettingLauncher(getContext())
                             .setDestination(ButtonNavigationSettingsFragment.class.getName())

tests/robotests/res/xml-mcc997/location_settings.xml

@@ -0,0 +1,36 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2024 The Android Open Source 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.
+-->
+
+<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:settings="http://schemas.android.com/apk/res-auto"
+    android:key="fake_title_key"
+    android:title="screen_title">
+
+    <Preference
+        android:key="key1"
+        android:title="title"
+        android:icon="@drawable/ic_android"
+        android:summary="summary1"
+        settings:controller="com.android.settings.core.UnavailablePreferenceController"/>
+
+    <Preference
+        android:key="key2"
+        android:title="title"
+        android:icon="@drawable/ic_android"
+        android:summary="summary2"
+        settings:controller="com.android.settings.core.UnavailablePreferenceController"/>
+
+</PreferenceScreen>

tests/robotests/src/com/android/settings/core/PreferenceControllerListHelperTest.java

@@ -20,6 +20,8 @@ import static com.google.common.truth.Truth.assertThat;
 
 import android.content.Context;
 
+import androidx.preference.PreferenceManager;
+
 import com.android.settings.R;
 import com.android.settings.slices.FakePreferenceController;
 import com.android.settingslib.core.AbstractPreferenceController;
@@ -38,10 +40,12 @@ import java.util.List;
 public class PreferenceControllerListHelperTest {
 
     private Context mContext;
+    private PreferenceManager mPreferenceManager;
 
     @Before
     public void setUp() {
         mContext = RuntimeEnvironment.application;
+        mPreferenceManager = new PreferenceManager(mContext);
     }
 
     @Test
@@ -68,6 +72,30 @@ public class PreferenceControllerListHelperTest {
         assertThat(controllers.get(0)).isInstanceOf(FakePreferenceController.class);
     }
 
+    @Test
+    @Config(qualifiers = "mcc999")
+    public void areAllPreferencesUnavailable_allAvailable() {
+        // All preferences have controllers indicating they are available.
+        assertThat(PreferenceControllerListHelper.areAllPreferencesUnavailable(mContext,
+                mPreferenceManager, R.xml.location_settings)).isFalse();
+    }
+
+    @Test
+    @Config(qualifiers = "mcc997")
+    public void areAllPreferencesUnavailable_allUnavailable() {
+        // All preferences have controllers indicating they are unavailable. (note the qualifier)
+        assertThat(PreferenceControllerListHelper.areAllPreferencesUnavailable(mContext,
+                mPreferenceManager, R.xml.location_settings)).isTrue();
+    }
+
+    @Test
+    @Config(qualifiers = "mcc999")
+    public void areAllPreferencesUnavailable_noControllersShouldAssumeAvailable() {
+        // None of the preferences have controllers, so they are assumed available.
+        assertThat(PreferenceControllerListHelper.areAllPreferencesUnavailable(mContext,
+                mPreferenceManager, R.xml.display_settings)).isFalse();
+    }
+
     @Test
     public void filterControllers_noFilter_shouldReturnSameList() {
         final List<BasePreferenceController> controllers = new ArrayList<>();

tests/robotests/src/com/android/settings/core/UnavailablePreferenceController.java

@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2024 The Android Open Source 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.core;
+
+import android.content.Context;
+
+public class UnavailablePreferenceController extends BasePreferenceController {
+
+    public UnavailablePreferenceController(Context context, String preferenceKey) {
+        super(context, preferenceKey);
+    }
+
+    @Override
+    public int getAvailabilityStatus() {
+        return UNSUPPORTED_ON_DEVICE;
+    }
+
+}