Merge changes from topic "regional_preference_metrics" into udc-dev

* changes:
  [Regional Pref] Remove Calendar controller and related Fragement
  [Regional Pref] 1. Add metrics for user changes the First day of week 2. Refactor to Settings design
  [Regional Pref] 1. Add metrics for user changes the Temperature unit 2. Refactor to Settings design

res/values/arrays.xml

@@ -1389,20 +1389,6 @@
         <item>sat</item>
     </string-array>
 
-    <!-- A list for all supported calendar types. [DO NOT TRANSLATE] -->
-    <string-array name="calendar_type">
-        <item>default</item>
-        <item>chinese</item>
-        <item>dangi</item>
-        <item>hebrew</item>
-        <item>indian</item>
-        <item>islamic</item>
-        <item>islamic-rgsa</item>
-        <item>islamic-tbla</item>
-        <item>islamic-umalqura</item>
-        <item>persian</item>
-    </string-array>
-
     <!-- Screen flash notification color when activating -->
     <array name="screen_flash_notification_preset_opacity_colors">
         <item>@color/screen_flash_preset_opacity_color_01</item>

res/values/strings.xml

@@ -401,8 +401,6 @@
     <string name="regional_preferences_option_page_sub_title">Apps will use your regional preferences where possible.</string>
     <!-- The title of menu entry of Temperature unit preference. [CHAR LIMIT=50] -->
     <string name="temperature_preferences_title">Temperature</string>
-    <!-- The title of the  menu entry of Calendar type preference. [CHAR LIMIT=50]  -->
-    <string name="calendar_preferences_title">Calendar</string>
     <!-- The title of the  menu entry of First day of week preference. [CHAR LIMIT=50]  -->
     <string name="first_day_of_week_preferences_title">First day of week</string>
     <!-- The title of the menu entry of Numbers system preference. [CHAR LIMIT=50]  -->

res/xml/regional_preference_main_page.xml

@@ -27,29 +27,18 @@
         android:title="@string/temperature_preferences_title"
         android:summary="@string/default_string_of_regional_preference"
         settings:controller="com.android.settings.regionalpreferences.TemperatureUnitController"
-        settings:fragment="com.android.settings.regionalpreferences.RegionalPreferencesFragment">
+        settings:fragment="com.android.settings.regionalpreferences.TemperatureUnitFragment">
         <extra
             android:name="arg_key_regional_preference"
             android:value="mu" />
     </Preference>
 
-    <Preference
-        android:key="key_calendar_type"
-        android:title="@string/calendar_preferences_title"
-        android:summary="@string/default_string_of_regional_preference"
-        settings:controller="com.android.settings.regionalpreferences.CalendarTypeController"
-        settings:fragment="com.android.settings.regionalpreferences.RegionalPreferencesFragment">
-        <extra
-            android:name="arg_key_regional_preference"
-            android:value="ca" />
-    </Preference>
-
     <Preference
         android:key="key_first_day_of_week"
         android:title="@string/first_day_of_week_preferences_title"
         android:summary="@string/default_string_of_regional_preference"
         settings:controller="com.android.settings.regionalpreferences.FirstDayOfWeekController"
-        settings:fragment="com.android.settings.regionalpreferences.RegionalPreferencesFragment">
+        settings:fragment="com.android.settings.regionalpreferences.FirstDayOfWeekItemFragment">
         <extra
             android:name="arg_key_regional_preference"
             android:value="fw" />

res/xml/regional_preferences_first_day_of_week.xml

@@ -0,0 +1,32 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2023 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:title="@string/first_day_of_week_preferences_title">
+
+    <com.android.settingslib.widget.TopIntroPreference
+        android:title="@string/regional_preferences_option_page_sub_title"
+        android:persistent="false" />
+
+    <PreferenceCategory
+        android:key="first_day_of_week_item_category"
+        android:title="@string/summary_placeholder"
+        android:layout="@layout/preference_category_no_label"
+        settings:controller="com.android.settings.regionalpreferences.FirstDayOfWeekItemCategoryController"/>
+
+</PreferenceScreen>

res/xml/regional_preferences_temperature.xml

@@ -13,10 +13,20 @@
      See the License for the specific language governing permissions and
      limitations under the License.
 -->
-<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
+
+<PreferenceScreen
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:settings="http://schemas.android.com/apk/res-auto"
+    android:title="@string/temperature_preferences_title">
 
     <com.android.settingslib.widget.TopIntroPreference
-        android:key="key_option_page_sub_title"
         android:title="@string/regional_preferences_option_page_sub_title"
         android:persistent="false" />
+
+    <PreferenceCategory
+        android:key="temperature_unit_category"
+        android:title="@string/summary_placeholder"
+        android:layout="@layout/preference_category_no_label"
+        settings:controller="com.android.settings.regionalpreferences.TemperatureUnitCategoryController"/>
+
 </PreferenceScreen>

src/com/android/settings/regionalpreferences/CalendarTypeController.java

@@ -1,71 +0,0 @@
-/*
- * Copyright (C) 2022 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.regionalpreferences;
-
-import android.content.Context;
-import android.os.SystemProperties;
-import android.provider.Settings;
-
-import com.android.settings.core.BasePreferenceController;
-
-import java.util.Locale;
-
-/**
- * A controller for the entry of Calendar types' page
- */
-public class CalendarTypeController extends BasePreferenceController {
-    private static final String CALENDAR_FEATURE_PROPERTY =
-            "i18n-feature-locale-preference-calendar";
-    private static final String TAG = CalendarTypeController.class.getSimpleName();
-    public CalendarTypeController(Context context, String preferenceKey) {
-        super(context, preferenceKey);
-    }
-
-    /**
-     * @return {@link AvailabilityStatus} for the Setting. This status is used to determine if the
-     * Setting should be shown or disabled in Settings. Further, it can be used to produce
-     * appropriate error / warning Slice in the case of unavailability.
-     * </p>
-     * The status is used for the convenience methods: {@link #isAvailable()}, {@link
-     * #isSupported()}
-     * </p>
-     * The inherited class doesn't need to check work profile if android:forWork="true" is set in
-     * preference xml.
-     */
-    @Override
-    public int getAvailabilityStatus() {
-        return SystemProperties.getBoolean(CALENDAR_FEATURE_PROPERTY, false)
-                ? AVAILABLE : CONDITIONALLY_UNAVAILABLE;
-    }
-
-    @Override
-    public CharSequence getSummary() {
-        String record = Settings.System.getString(
-                mContext.getContentResolver(), Settings.System.LOCALE_PREFERENCES);
-        String result = "";
-        if (record != null) {
-            result = LocalePreferences.getCalendarType(Locale.forLanguageTag(record), false);
-        }
-
-        if (result.isEmpty()) {
-            result = LocalePreferences.getCalendarType(false);
-        }
-
-        String inputStr = result.isEmpty() ? RegionalPreferencesDataUtils.DEFAULT_VALUE : result;
-        return RegionalPreferencesDataUtils.calendarConverter(mContext, inputStr);
-    }
-}

src/com/android/settings/regionalpreferences/FirstDayOfWeekItemCategoryController.java

@@ -0,0 +1,61 @@
+/**
+ * Copyright (C) 2023 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.regionalpreferences;
+
+import android.content.Context;
+import android.util.Log;
+
+import androidx.preference.PreferenceCategory;
+import androidx.preference.PreferenceScreen;
+
+import com.android.settings.widget.PreferenceCategoryController;
+
+/** Category preference controller for first day of week preferences. */
+public class FirstDayOfWeekItemCategoryController extends PreferenceCategoryController {
+
+    private static final String LOG_TAG = "FirstDayOfWeekItemCategoryController";
+    private static final String KEY_PREFERENCE_CATEGORY_FIRST_DAY_OF_WEEK_ITEM =
+            "first_day_of_week_item_category";
+    private static final String KEY_PREFERENCE_FIRST_DAY_OF_WEEK_ITEM =
+            "first_day_of_week_item_list";
+
+    private PreferenceCategory mPreferenceCategory;
+    private FirstDayOfWeekItemListController mFirstDayOfWeekItemListController;
+
+    public FirstDayOfWeekItemCategoryController(Context context, String key) {
+        super(context, key);
+    }
+
+    @Override
+    public int getAvailabilityStatus() {
+        return AVAILABLE;
+    }
+
+    @Override
+    public void displayPreference(PreferenceScreen screen) {
+        super.displayPreference(screen);
+        mPreferenceCategory = screen.findPreference(KEY_PREFERENCE_CATEGORY_FIRST_DAY_OF_WEEK_ITEM);
+        if (mPreferenceCategory == null) {
+            Log.d(LOG_TAG, "displayPreference(), Can not find the category.");
+            return;
+        }
+        mPreferenceCategory.setVisible(isAvailable());
+        mFirstDayOfWeekItemListController = new FirstDayOfWeekItemListController(mContext,
+                KEY_PREFERENCE_FIRST_DAY_OF_WEEK_ITEM);
+        mFirstDayOfWeekItemListController.displayPreference(screen);
+    }
+}

src/com/android/settings/regionalpreferences/FirstDayOfWeekItemFragment.java

@@ -0,0 +1,64 @@
+/**
+ * Copyright (C) 2023 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.regionalpreferences;
+
+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.search.SearchIndexable;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/** Main fragment to display first day of week. */
+@SearchIndexable(forTarget = SearchIndexable.ALL & ~SearchIndexable.ARC)
+public class FirstDayOfWeekItemFragment extends DashboardFragment {
+
+    private static final String LOG_TAG = "FirstDayOfWeekItemFragment";
+    private static final String KEY_PREFERENCE_CATEGORY_FIRST_DAY_OF_WEEK_ITEM =
+            "first_day_of_week_item_category";
+
+    @Override
+    protected int getPreferenceScreenResId() {
+        return R.xml.regional_preferences_first_day_of_week;
+    }
+
+    @Override
+    public int getMetricsCategory() {
+        return SettingsEnums.FIRST_DAY_OF_WEEK_PREFERENCE;
+    }
+
+    @Override
+    protected String getLogTag() {
+        return LOG_TAG;
+    }
+
+    @Override
+    protected List<AbstractPreferenceController> createPreferenceControllers(Context context) {
+        final List<AbstractPreferenceController> controllers = new ArrayList<>();
+        controllers.add(new FirstDayOfWeekItemCategoryController(context,
+                KEY_PREFERENCE_CATEGORY_FIRST_DAY_OF_WEEK_ITEM));
+        return controllers;
+    }
+
+    public static final BaseSearchIndexProvider SEARCH_INDEX_DATA_PROVIDER =
+            new BaseSearchIndexProvider(R.xml.regional_preferences_first_day_of_week);
+}

src/com/android/settings/regionalpreferences/FirstDayOfWeekItemListController.java

@@ -0,0 +1,66 @@
+/**
+ * Copyright (C) 2023 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.regionalpreferences;
+
+import android.app.settings.SettingsEnums;
+import android.content.Context;
+
+import com.android.settings.R;
+
+/** A controller for handling all first day of week preferences. */
+public class FirstDayOfWeekItemListController extends
+        RegionalPreferenceListBasePreferenceController {
+
+    private static final String KEY_PREFERENCE_CATEGORY_FIRST_DAY_OF_WEEK_ITEM =
+            "first_day_of_week_item_category";
+    private static final String KEY_PREFERENCE_FIRST_DAY_OF_WEEK_ITEM =
+            "first_day_of_week_item_list";
+
+    public FirstDayOfWeekItemListController(Context context, String key) {
+        super(context, key);
+    }
+
+    @Override
+    protected String getPreferenceTitle(String item) {
+        return RegionalPreferencesDataUtils.dayConverter(mContext, item);
+    }
+
+    @Override
+    protected String getPreferenceCategoryKey() {
+        return KEY_PREFERENCE_CATEGORY_FIRST_DAY_OF_WEEK_ITEM;
+    }
+
+    @Override
+    public String getPreferenceKey() {
+        return KEY_PREFERENCE_FIRST_DAY_OF_WEEK_ITEM;
+    }
+
+    @Override
+    protected String getExtensionTypes() {
+        return ExtensionTypes.FIRST_DAY_OF_WEEK;
+    }
+
+    @Override
+    protected String[] getUnitValues() {
+        return mContext.getResources().getStringArray(R.array.first_day_of_week);
+    }
+
+    @Override
+    protected int getMetricsActionKey() {
+        return SettingsEnums.ACTION_SET_FIRST_DAY_OF_WEEK;
+    }
+}

src/com/android/settings/regionalpreferences/OWNERS

@@ -0,0 +1,7 @@
+allenwtsu@google.com
+calvinpan@google.com
+danielwbhuang@google.com
+goldmanj@google.com
+joshhou@google.com
+zoeychen@google.com
+tomhsu@google.com

src/com/android/settings/regionalpreferences/RegionalPreferenceListBasePreferenceController.java

@@ -0,0 +1,103 @@
+/**
+ * Copyright (C) 2023 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.regionalpreferences;
+
+import android.app.settings.SettingsEnums;
+import android.content.Context;
+import android.util.Log;
+
+import androidx.preference.Preference;
+import androidx.preference.PreferenceCategory;
+import androidx.preference.PreferenceScreen;
+
+import com.android.settings.core.BasePreferenceController;
+import com.android.settings.overlay.FeatureFactory;
+import com.android.settings.widget.TickButtonPreference;
+import com.android.settingslib.core.instrumentation.MetricsFeatureProvider;
+
+/** A base controller for handling all regional preferences controllers. */
+public abstract class RegionalPreferenceListBasePreferenceController extends
+        BasePreferenceController {
+
+    private final MetricsFeatureProvider mMetricsFeatureProvider;
+    private PreferenceCategory mPreferenceCategory;
+
+    public RegionalPreferenceListBasePreferenceController(Context context, String preferenceKey) {
+        super(context, preferenceKey);
+        mMetricsFeatureProvider = FeatureFactory.getFactory(context).getMetricsFeatureProvider();
+    }
+
+    @Override
+    public void displayPreference(PreferenceScreen screen) {
+        super.displayPreference(screen);
+        mPreferenceCategory = screen.findPreference(getPreferenceCategoryKey());
+        initPreferences();
+    }
+
+    private void initPreferences() {
+        if (mPreferenceCategory == null) {
+            return;
+        }
+
+        String[] unitValues = getUnitValues();
+
+        for (int i = 0; i < unitValues.length; i++) {
+            TickButtonPreference pref = new TickButtonPreference(mContext);
+            mPreferenceCategory.addPreference(pref);
+            final String item = unitValues[i];
+            pref.setTitle(getPreferenceTitle(item));
+            pref.setKey(item);
+            pref.setOnPreferenceClickListener(clickedPref -> {
+                setSelected(pref);
+                RegionalPreferencesDataUtils.savePreference(mContext, getExtensionTypes(), item);
+                mMetricsFeatureProvider.action(mContext, getMetricsActionKey(), item);
+                return true;
+            });
+            String value = RegionalPreferencesDataUtils.getDefaultUnicodeExtensionData(mContext,
+                    getExtensionTypes());
+            pref.setSelected(!value.isEmpty() && item.equals(value));
+        }
+    }
+
+    private void setSelected(TickButtonPreference preference) {
+        for (int i = 0; i < mPreferenceCategory.getPreferenceCount(); i++) {
+            TickButtonPreference pref = (TickButtonPreference) mPreferenceCategory.getPreference(i);
+            if (pref.getKey().equals(preference.getKey())) {
+                pref.setSelected(true);
+                continue;
+            }
+            pref.setSelected(false);
+        }
+    }
+
+    @Override
+    public int getAvailabilityStatus() {
+        return AVAILABLE;
+    }
+
+    protected abstract String getPreferenceTitle(String item);
+
+    protected abstract String getPreferenceCategoryKey();
+
+    protected abstract String getExtensionTypes();
+
+    protected abstract String[] getUnitValues();
+
+    protected abstract int getMetricsActionKey();
+
+
+}

src/com/android/settings/regionalpreferences/RegionalPreferencesDataUtils.java

@@ -29,7 +29,6 @@ import java.util.Locale;
 
 /** Provides utils for regional preferences. */
 public class RegionalPreferencesDataUtils {
-    static final String DISPLAY_KEYWORD_OF_CALENDAR = "calendar";
     static final String DEFAULT_VALUE = "default";
 
     static String getDefaultUnicodeExtensionData(Context contxt, String type) {
@@ -86,18 +85,6 @@ public class RegionalPreferencesDataUtils {
         return addUnicodeKeywordToLocale(Locale.forLanguageTag(languageTag), type, value);
     }
 
-    static String calendarConverter(Context context, String calendarType) {
-        if (calendarType.equals(DEFAULT_VALUE)) {
-            return context.getString(R.string.default_string_of_regional_preference);
-        }
-
-        Locale locale = new Locale.Builder()
-                .setUnicodeLocaleKeyword(ExtensionTypes.CALENDAR, calendarType)
-                .build();
-        return ULocale.getDisplayKeywordValue(locale.toLanguageTag(), DISPLAY_KEYWORD_OF_CALENDAR,
-                ULocale.forLocale(Locale.getDefault(Locale.Category.FORMAT)));
-    }
-
     static String temperatureUnitsConverter(Context context, String unit) {
         switch (unit) {
             case LocalePreferences.TemperatureUnit.CELSIUS:

src/com/android/settings/regionalpreferences/RegionalPreferencesFragment.java

@@ -1,143 +0,0 @@
-/*
- * Copyright (C) 2023 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.regionalpreferences;
-
-import android.app.settings.SettingsEnums;
-import android.os.Bundle;
-import android.util.Log;
-import android.view.LayoutInflater;
-import android.view.View;
-import android.view.ViewGroup;
-
-import androidx.annotation.VisibleForTesting;
-import androidx.preference.Preference;
-import androidx.preference.PreferenceScreen;
-
-import com.android.settings.R;
-import com.android.settings.SettingsPreferenceFragment;
-import com.android.settings.widget.TickButtonPreference;
-
-/** A fragment to include each kind of regional preferences. */
-public class RegionalPreferencesFragment extends SettingsPreferenceFragment {
-    private static final String TAG = RegionalPreferencesFragment.class.getSimpleName();
-
-    private PreferenceScreen mPreferenceScreen;
-    private String mTitle = "";
-    @VisibleForTesting
-    String mType = "";
-
-    private String[] initializeUIdata(String type) {
-        switch(type) {
-            case ExtensionTypes.TEMPERATURE_UNIT:
-                mTitle = getPrefContext().getString(R.string.temperature_preferences_title);
-                return getPrefContext().getResources().getStringArray(R.array.temperature_units);
-            case ExtensionTypes.CALENDAR:
-                mTitle = getPrefContext().getString(R.string.calendar_preferences_title);
-                return getPrefContext().getResources().getStringArray(R.array.calendar_type);
-            case ExtensionTypes.FIRST_DAY_OF_WEEK:
-                mTitle = getPrefContext().getString(R.string.first_day_of_week_preferences_title);
-                return getPrefContext().getResources().getStringArray(R.array.first_day_of_week);
-            default:
-                mTitle = getPrefContext().getString(R.string.regional_preferences_title);
-                return new String[0];
-        }
-    }
-
-    @Override
-    public boolean onPreferenceTreeClick(Preference preference) {
-        // The first preference is TopIntroPreference
-        for (int i = 1; i < mPreferenceScreen.getPreferenceCount(); i++) {
-            TickButtonPreference pref = (TickButtonPreference) mPreferenceScreen.getPreference(i);
-            Log.i(TAG, "[onPreferenceClick] key is " + pref.getKey());
-            if (pref.getKey().equals(preference.getKey())) {
-                pref.setSelected(true);
-                RegionalPreferencesDataUtils.savePreference(
-                        getPrefContext(),
-                        mType,
-                        preference.getKey().equals(
-                                RegionalPreferencesDataUtils.DEFAULT_VALUE)
-                                ? null : preference.getKey());
-                continue;
-            }
-            pref.setSelected(false);
-        }
-        return true;
-    }
-
-    @Override
-    public void onCreate(Bundle icicle) {
-        super.onCreate(icicle);
-        Bundle bundle = getArguments();
-        String type = bundle.getString(
-                RegionalPreferencesEntriesFragment.ARG_KEY_REGIONAL_PREFERENCE, "");
-        if (type.isEmpty()) {
-            Log.w(TAG, "There is no type name.");
-            finish();
-        }
-        mType = type;
-        addPreferencesFromResource(R.xml.regional_preference_content_page);
-        mPreferenceScreen = getPreferenceScreen();
-    }
-
-    @Override
-    public View onCreateView(LayoutInflater inflater, ViewGroup container,
-            Bundle savedInstanceState) {
-        String[] uiData = initializeUIdata(mType);
-        for (String item : uiData) {
-            TickButtonPreference pref = new TickButtonPreference(getPrefContext());
-            if (mType.equals(ExtensionTypes.FIRST_DAY_OF_WEEK)) {
-                pref.setTitle(RegionalPreferencesDataUtils.dayConverter(
-                        getPrefContext(), item));
-            } else if (mType.equals(ExtensionTypes.TEMPERATURE_UNIT)) {
-                pref.setTitle(RegionalPreferencesDataUtils.temperatureUnitsConverter(
-                        getPrefContext(), item));
-            } else if (mType.equals(ExtensionTypes.CALENDAR)) {
-                pref.setTitle(RegionalPreferencesDataUtils.calendarConverter(
-                        getPrefContext(), item));
-            } else {
-                Log.d(TAG, "Finish this page due to no suitable type.");
-                finish();
-            }
-
-            String value = RegionalPreferencesDataUtils.getDefaultUnicodeExtensionData(
-                    getPrefContext(), mType);
-            pref.setKey(item);
-            pref.setSelected(!value.isEmpty() && item.equals(value));
-            mPreferenceScreen.addPreference(pref);
-        }
-        return super.onCreateView(inflater, container, savedInstanceState);
-    }
-
-    @Override
-    public void onStart() {
-        super.onStart();
-        getActivity().setTitle(mTitle);
-    }
-
-    @Override
-    public int getMetricsCategory() {
-        switch(mType) {
-            case ExtensionTypes.CALENDAR:
-                return SettingsEnums.CALENDAR_PREFERENCE;
-            case ExtensionTypes.FIRST_DAY_OF_WEEK:
-                return SettingsEnums.FIRST_DAY_OF_WEEK_PREFERENCE;
-            default:
-                return SettingsEnums.TEMPERATURE_PREFERENCE;
-        }
-    }
-
-}

src/com/android/settings/regionalpreferences/TemperatureUnitCategoryController.java

@@ -0,0 +1,60 @@
+/**
+ * Copyright (C) 2023 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.regionalpreferences;
+
+import android.content.Context;
+import android.util.Log;
+
+import androidx.preference.PreferenceCategory;
+import androidx.preference.PreferenceScreen;
+
+import com.android.settings.widget.PreferenceCategoryController;
+
+/** Category preference controller for temperature preferences. */
+public class TemperatureUnitCategoryController extends PreferenceCategoryController {
+
+    private static final String LOG_TAG = "TemperatureUnitCategoryController";
+    private static final String KEY_PREFERENCE_CATEGORY_TEMPERATURE_UNIT =
+            "temperature_unit_category";
+    private static final String KEY_PREFERENCE_TEMPERATURE_UNIT = "temperature_unit_list";
+
+    private PreferenceCategory mPreferenceCategory;
+    private TemperatureUnitListController mTemperatureUnitListController;
+
+    public TemperatureUnitCategoryController(Context context, String key) {
+        super(context, key);
+    }
+
+    @Override
+    public int getAvailabilityStatus() {
+        return AVAILABLE;
+    }
+
+    @Override
+    public void displayPreference(PreferenceScreen screen) {
+        super.displayPreference(screen);
+        mPreferenceCategory = screen.findPreference(KEY_PREFERENCE_CATEGORY_TEMPERATURE_UNIT);
+        if (mPreferenceCategory == null) {
+            Log.d(LOG_TAG, "displayPreference(), Can not find the category.");
+            return;
+        }
+        mPreferenceCategory.setVisible(isAvailable());
+        mTemperatureUnitListController = new TemperatureUnitListController(mContext,
+                KEY_PREFERENCE_TEMPERATURE_UNIT);
+        mTemperatureUnitListController.displayPreference(screen);
+    }
+}

src/com/android/settings/regionalpreferences/TemperatureUnitFragment.java

@@ -0,0 +1,64 @@
+/**
+ * Copyright (C) 2023 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.regionalpreferences;
+
+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.search.SearchIndexable;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/** Main fragment to display temperature preferences. */
+@SearchIndexable(forTarget = SearchIndexable.ALL & ~SearchIndexable.ARC)
+public class TemperatureUnitFragment extends DashboardFragment {
+
+    private static final String LOG_TAG = "TemperatureUnitFragment";
+    private static final String KEY_PREFERENCE_CATEGORY_TEMPERATURE_UNIT =
+            "temperature_unit_category";
+
+    @Override
+    protected int getPreferenceScreenResId() {
+        return R.xml.regional_preferences_temperature;
+    }
+
+    @Override
+    public int getMetricsCategory() {
+        return SettingsEnums.TEMPERATURE_PREFERENCE;
+    }
+
+    @Override
+    protected String getLogTag() {
+        return LOG_TAG;
+    }
+
+    @Override
+    protected List<AbstractPreferenceController> createPreferenceControllers(Context context) {
+        final List<AbstractPreferenceController> controllers = new ArrayList<>();
+        controllers.add(new TemperatureUnitCategoryController(context,
+                KEY_PREFERENCE_CATEGORY_TEMPERATURE_UNIT));
+        return controllers;
+    }
+
+    public static final BaseSearchIndexProvider SEARCH_INDEX_DATA_PROVIDER =
+            new BaseSearchIndexProvider(R.xml.regional_preferences_temperature);
+}

src/com/android/settings/regionalpreferences/TemperatureUnitListController.java

@@ -0,0 +1,64 @@
+/**
+ * Copyright (C) 2023 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.regionalpreferences;
+
+import android.app.settings.SettingsEnums;
+import android.content.Context;
+
+import com.android.settings.R;
+
+/** A controller for handling all temperature preferences. */
+public class TemperatureUnitListController extends RegionalPreferenceListBasePreferenceController {
+
+    private static final String KEY_PREFERENCE_CATEGORY_TEMPERATURE_UNIT =
+            "temperature_unit_category";
+    private static final String KEY_PREFERENCE_TEMPERATURE_UNIT = "temperature_unit_list";
+
+    public TemperatureUnitListController(Context context, String key) {
+        super(context, key);
+    }
+
+    @Override
+    protected String getPreferenceTitle(String item) {
+        return RegionalPreferencesDataUtils.temperatureUnitsConverter(mContext, item);
+    }
+
+    @Override
+    protected String getPreferenceCategoryKey() {
+        return KEY_PREFERENCE_CATEGORY_TEMPERATURE_UNIT;
+    }
+
+    @Override
+    public String getPreferenceKey() {
+        return KEY_PREFERENCE_TEMPERATURE_UNIT;
+    }
+
+    @Override
+    protected String getExtensionTypes() {
+        return ExtensionTypes.TEMPERATURE_UNIT;
+    }
+
+    @Override
+    protected String[] getUnitValues() {
+        return mContext.getResources().getStringArray(R.array.temperature_units);
+    }
+
+    @Override
+    protected int getMetricsActionKey() {
+        return SettingsEnums.ACTION_SET_TEMPERATURE_UNIT;
+    }
+}

tests/unit/src/com/android/settings/regionalpreferences/CalendarTypeControllerTest.java

@@ -1,107 +0,0 @@
-/*
- * Copyright (C) 2022 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.regionalpreferences;
-
-import static org.junit.Assert.assertEquals;
-
-import android.content.Context;
-import android.icu.util.ULocale;
-import android.provider.Settings;
-
-import androidx.test.core.app.ApplicationProvider;
-
-import com.android.settings.testutils.ResourcesUtils;
-
-import org.junit.After;
-import org.junit.Before;
-import org.junit.Test;
-
-import java.util.Locale;
-
-public class CalendarTypeControllerTest {
-    private Context mApplicationContext;
-    private CalendarTypeController mController;
-    private String mCacheProviderContent = "";
-    private Locale mCacheLocale;
-
-    @Before
-    public void setUp() throws Exception {
-        mApplicationContext = ApplicationProvider.getApplicationContext();
-        mController = new CalendarTypeController(mApplicationContext, "key");
-        mCacheProviderContent = Settings.System.getString(
-                mApplicationContext.getContentResolver(), Settings.System.LOCALE_PREFERENCES);
-        mCacheLocale = Locale.getDefault(Locale.Category.FORMAT);
-    }
-
-    @After
-    public void tearDown() throws Exception {
-        RegionalPreferenceTestUtils.setSettingsProviderContent(
-                mApplicationContext, mCacheProviderContent);
-        Locale.setDefault(mCacheLocale);
-    }
-
-    @Test
-    public void getSummary_hasProviderValue_resultIsChineseCalendar() {
-        RegionalPreferenceTestUtils.setSettingsProviderContent(
-                mApplicationContext, "und-u-ca-chinese");
-
-        String summary = mController.getSummary().toString();
-
-        assertEquals(getDisplayKeywordValue(LocalePreferences.CalendarType.CHINESE), summary);
-    }
-
-    @Test
-    public void getSummary_hasProviderValue_resultIsDangiCalendar() {
-        RegionalPreferenceTestUtils.setSettingsProviderContent(
-                mApplicationContext, "und-u-ca-dangi");
-
-        String summary = mController.getSummary().toString();
-
-        assertEquals(getDisplayKeywordValue(LocalePreferences.CalendarType.DANGI), summary);
-    }
-
-    @Test
-    public void getSummary_noProviderValueButHasDefaultLocaleWithSubtag_resultIsChineseCalendar() {
-        RegionalPreferenceTestUtils.setSettingsProviderContent(mApplicationContext, "");
-        Locale.setDefault(Locale.forLanguageTag("en-US-u-ca-chinese"));
-
-        String summary = mController.getSummary().toString();
-
-        assertEquals(getDisplayKeywordValue(LocalePreferences.CalendarType.CHINESE), summary);
-    }
-
-    @Test
-    public void getSummary_noProviderValueAndDefaultLocaleWithoutSubtag_resultIsEmpty() {
-        RegionalPreferenceTestUtils.setSettingsProviderContent(mApplicationContext, "");
-        Locale.setDefault(Locale.forLanguageTag("en-US"));
-
-        String summary = mController.getSummary().toString();
-
-        assertEquals(ResourcesUtils.getResourcesString(
-                mApplicationContext, "default_string_of_regional_preference"), summary);
-    }
-
-    private static String getDisplayKeywordValue(String value) {
-        String languageTag = new Locale.Builder()
-                .setUnicodeLocaleKeyword(
-                        ExtensionTypes.CALENDAR, value).build().toLanguageTag();
-        return ULocale.getDisplayKeywordValue(
-                languageTag,
-                RegionalPreferencesDataUtils.DISPLAY_KEYWORD_OF_CALENDAR,
-                ULocale.forLocale(Locale.getDefault(Locale.Category.FORMAT)));
-    }
-}

tests/unit/src/com/android/settings/regionalpreferences/FirstDayOfWeekItemListControllerTest.java

@@ -0,0 +1,124 @@
+/**
+ * Copyright (C) 2023 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.regionalpreferences;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import static org.mockito.Mockito.spy;
+
+import android.content.Context;
+import android.os.LocaleList;
+import android.os.Looper;
+import android.provider.Settings;
+
+import com.android.internal.app.LocalePicker;
+import com.android.settings.widget.TickButtonPreference;
+
+import androidx.preference.PreferenceManager;
+import androidx.preference.Preference;
+import androidx.preference.PreferenceCategory;
+import androidx.preference.PreferenceScreen;
+import androidx.test.core.app.ApplicationProvider;
+import androidx.test.ext.junit.runners.AndroidJUnit4;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.MockitoAnnotations;
+
+import java.util.Locale;
+
+@RunWith(AndroidJUnit4.class)
+public class FirstDayOfWeekItemListControllerTest {
+
+    private static final String KEY_PREFERENCE_CATEGORY_FIRST_DAY_OF_WEEK_ITEM =
+            "first_day_of_week_item_category";
+    private static final String KEY_PREFERENCE_FIRST_DAY_OF_WEEK_ITEM =
+            "first_day_of_week_item_list";
+
+    private Context mContext;
+    private PreferenceManager mPreferenceManager;
+    private PreferenceCategory mPreferenceCategory;
+    private PreferenceScreen mPreferenceScreen;
+    private FirstDayOfWeekItemListController mController;
+    private LocaleList mCacheLocaleList;
+    private Locale mCacheLocale;
+    private String mCacheProviderContent = "";
+
+    @Before
+    public void setUp() throws Exception {
+        MockitoAnnotations.initMocks(this);
+        mContext = spy(ApplicationProvider.getApplicationContext());
+        if (Looper.myLooper() == null) {
+            Looper.prepare();
+        }
+        mPreferenceManager = new PreferenceManager(mContext);
+        mPreferenceScreen = mPreferenceManager.createPreferenceScreen(mContext);
+        mPreferenceCategory = new PreferenceCategory(mContext);
+        mPreferenceCategory.setKey(KEY_PREFERENCE_CATEGORY_FIRST_DAY_OF_WEEK_ITEM);
+        mPreferenceScreen.addPreference(mPreferenceCategory);
+        mController = new FirstDayOfWeekItemListController(mContext,
+                KEY_PREFERENCE_FIRST_DAY_OF_WEEK_ITEM);
+        mController.displayPreference(mPreferenceScreen);
+        mCacheProviderContent = Settings.System.getString(
+                mContext.getContentResolver(), Settings.System.LOCALE_PREFERENCES);
+        mCacheLocale = Locale.getDefault(Locale.Category.FORMAT);
+        mCacheLocaleList = LocaleList.getDefault();
+    }
+
+    @After
+    public void tearDown() throws Exception {
+        RegionalPreferenceTestUtils.setSettingsProviderContent(
+                mContext, mCacheProviderContent);
+        Locale.setDefault(mCacheLocale);
+        LocalePicker.updateLocales(mCacheLocaleList);
+    }
+
+    @Test
+    public void displayPreference_setSelectPreferredFirstDayOfWeekIsDefault() {
+        TickButtonPreference pref = (TickButtonPreference) mPreferenceCategory.getPreference(0);
+        pref.performClick();
+        String record = Settings.System.getString(
+                mContext.getContentResolver(), Settings.System.LOCALE_PREFERENCES);
+
+        assertThat(pref.getKey()).isEqualTo("default");
+        assertThat(record).contains("default");
+    }
+
+    @Test
+    public void displayPreference_setSelectPreferredFirstDayOfWeekIsSunday() {
+        TickButtonPreference pref = (TickButtonPreference) mPreferenceCategory.getPreference(1);
+        pref.performClick();
+        String record = Settings.System.getString(
+                mContext.getContentResolver(), Settings.System.LOCALE_PREFERENCES);
+
+        assertThat(pref.getKey()).isEqualTo("sun");
+        assertThat(record).contains("sun");
+    }
+
+    @Test
+    public void displayPreference_setSelectPreferredFirstDayOfWeekIsMonday() {
+        TickButtonPreference pref = (TickButtonPreference) mPreferenceCategory.getPreference(2);
+        pref.performClick();
+        String record = Settings.System.getString(
+                mContext.getContentResolver(), Settings.System.LOCALE_PREFERENCES);
+
+        assertThat(pref.getKey()).isEqualTo("mon");
+        assertThat(record).contains("mon");
+    }
+}

tests/unit/src/com/android/settings/regionalpreferences/RegionalPreferencesFragmentTest.java

@@ -1,70 +0,0 @@
-/*
- * Copyright (C) 2023 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.regionalpreferences;
-
-import static org.junit.Assert.assertEquals;
-
-import android.app.settings.SettingsEnums;
-import android.os.Looper;
-
-import androidx.test.annotation.UiThreadTest;
-
-import org.junit.Before;
-import org.junit.Test;
-
-public class RegionalPreferencesFragmentTest {
-    private RegionalPreferencesFragment mFragment;
-
-    @Before
-    @UiThreadTest
-    public void setUp() throws Exception {
-        if (Looper.myLooper() == null) {
-            Looper.prepare();
-        }
-        mFragment = new RegionalPreferencesFragment();
-    }
-
-    @Test
-    @UiThreadTest
-    public void getMetricsCategory_typeIsCa_resultIsCalendarPreference() {
-        mFragment.mType = ExtensionTypes.CALENDAR;
-
-        int result = mFragment.getMetricsCategory();
-
-        assertEquals(SettingsEnums.CALENDAR_PREFERENCE, result);
-    }
-
-    @Test
-    @UiThreadTest
-    public void getMetricsCategory_typeIsFw_resultIsFirstDayOfWeekPreference() {
-        mFragment.mType = ExtensionTypes.FIRST_DAY_OF_WEEK;
-
-        int result = mFragment.getMetricsCategory();
-
-        assertEquals(SettingsEnums.FIRST_DAY_OF_WEEK_PREFERENCE, result);
-    }
-
-    @Test
-    @UiThreadTest
-    public void getMetricsCategory_typeIsMu_resultIsTemperaturePreference() {
-        mFragment.mType = ExtensionTypes.TEMPERATURE_UNIT;
-
-        int result = mFragment.getMetricsCategory();
-
-        assertEquals(SettingsEnums.TEMPERATURE_PREFERENCE, result);
-    }
-}

tests/unit/src/com/android/settings/regionalpreferences/TemperatureUnitListControllerTest.java

@@ -0,0 +1,121 @@
+/**
+ * Copyright (C) 2023 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.regionalpreferences;
+
+import static com.google.common.truth.Truth.assertThat;
+import static org.mockito.Mockito.spy;
+
+import android.content.Context;
+import android.os.LocaleList;
+import android.os.Looper;
+import android.provider.Settings;
+
+import com.android.internal.app.LocalePicker;
+import com.android.settings.widget.TickButtonPreference;
+
+import androidx.preference.PreferenceManager;
+import androidx.preference.Preference;
+import androidx.preference.PreferenceCategory;
+import androidx.preference.PreferenceScreen;
+import androidx.test.core.app.ApplicationProvider;
+import androidx.test.ext.junit.runners.AndroidJUnit4;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.MockitoAnnotations;
+
+import java.util.Locale;
+
+@RunWith(AndroidJUnit4.class)
+public class TemperatureUnitListControllerTest {
+
+    private static final String KEY_PREFERENCE_CATEGORY_TEMPERATURE_UNIT =
+            "temperature_unit_category";
+    private static final String KEY_PREFERENCE_TEMPERATURE_UNIT = "temperature_unit_list";
+
+    private Context mContext;
+    private PreferenceManager mPreferenceManager;
+    private PreferenceCategory mPreferenceCategory;
+    private PreferenceScreen mPreferenceScreen;
+    private TemperatureUnitListController mController;
+    private LocaleList mCacheLocaleList;
+    private Locale mCacheLocale;
+    private String mCacheProviderContent = "";
+
+    @Before
+    public void setUp() throws Exception {
+        MockitoAnnotations.initMocks(this);
+        mContext = spy(ApplicationProvider.getApplicationContext());
+        if (Looper.myLooper() == null) {
+            Looper.prepare();
+        }
+        mPreferenceManager = new PreferenceManager(mContext);
+        mPreferenceScreen = mPreferenceManager.createPreferenceScreen(mContext);
+        mPreferenceCategory = new PreferenceCategory(mContext);
+        mPreferenceCategory.setKey(KEY_PREFERENCE_CATEGORY_TEMPERATURE_UNIT);
+        mPreferenceScreen.addPreference(mPreferenceCategory);
+        mController = new TemperatureUnitListController(mContext, KEY_PREFERENCE_TEMPERATURE_UNIT);
+        mController.displayPreference(mPreferenceScreen);
+        mCacheProviderContent = Settings.System.getString(
+                mContext.getContentResolver(), Settings.System.LOCALE_PREFERENCES);
+        mCacheLocale = Locale.getDefault(Locale.Category.FORMAT);
+        mCacheLocaleList = LocaleList.getDefault();
+    }
+
+    @After
+    public void tearDown() throws Exception {
+        RegionalPreferenceTestUtils.setSettingsProviderContent(
+                mContext, mCacheProviderContent);
+        Locale.setDefault(mCacheLocale);
+        LocalePicker.updateLocales(mCacheLocaleList);
+    }
+
+    @Test
+    public void displayPreference_setSelectPreferredTemperatureUnitIsDefault() {
+        TickButtonPreference pref = (TickButtonPreference) mPreferenceCategory.getPreference(0);
+        pref.performClick();
+        String record = Settings.System.getString(
+                mContext.getContentResolver(), Settings.System.LOCALE_PREFERENCES);
+
+        assertThat(pref.getKey()).isEqualTo("default");
+        assertThat(record).contains("default");
+    }
+
+    @Test
+    public void displayPreference_setSelectPreferredTemperatureUnitIsCelsius() {
+        TickButtonPreference pref = (TickButtonPreference) mPreferenceCategory.getPreference(1);
+        pref.performClick();
+        String record = Settings.System.getString(
+                mContext.getContentResolver(), Settings.System.LOCALE_PREFERENCES);
+
+        assertThat(pref.getKey()).isEqualTo("celsius");
+        assertThat(record).contains("celsius");
+    }
+
+    @Test
+    public void displayPreference_setSelectPreferredTemperatureUnitIsFahrenhe() {
+        TickButtonPreference pref = (TickButtonPreference) mPreferenceCategory.getPreference(2);
+        pref.performClick();
+        String record = Settings.System.getString(
+                mContext.getContentResolver(), Settings.System.LOCALE_PREFERENCES);
+
+        assertThat(pref.getKey()).isEqualTo("fahrenhe");
+        assertThat(record).contains("fahrenhe");
+    }
+}