Merge "[Panlingual] Suggested locales update"
diff --git a/res/values/config.xml b/res/values/config.xml
index 7a2f641..ec239a2 100755
--- a/res/values/config.xml
+++ b/res/values/config.xml
@@ -573,4 +573,14 @@
 
     <!-- Whether to give option to add restricted profiles -->
     <bool name="config_offer_restricted_profiles">false</bool>
+
+    <!-- An array of packages for which Applications whose per-app locale cannot be changed. -->
+    <string-array name="config_disallowed_app_localeChange_packages" translatable="false">
+        <!--
+        <item>com.example.package.first</item>
+        <item>com.example.package.second</item>
+        <item>...</item>
+        -->
+    </string-array>
+
 </resources>
diff --git a/src/com/android/settings/accessibility/AccessibilitySettings.java b/src/com/android/settings/accessibility/AccessibilitySettings.java
index 8e8c7e4..c08e669 100644
--- a/src/com/android/settings/accessibility/AccessibilitySettings.java
+++ b/src/com/android/settings/accessibility/AccessibilitySettings.java
@@ -30,7 +30,6 @@
 import android.content.pm.ServiceInfo;
 import android.graphics.Color;
 import android.graphics.drawable.Drawable;
-import android.net.Uri;
 import android.os.Bundle;
 import android.os.Handler;
 import android.os.UserHandle;
@@ -147,7 +146,7 @@
     };
 
     @VisibleForTesting
-    final SettingsContentObserver mSettingsContentObserver;
+    final AccessibilitySettingsContentObserver mSettingsContentObserver;
 
     private final Map<String, PreferenceCategory> mCategoryToPrefCategoryMap =
             new ArrayMap<>();
@@ -171,12 +170,9 @@
         // Observe changes from accessibility selection menu
         shortcutFeatureKeys.add(Settings.Secure.ACCESSIBILITY_BUTTON_TARGETS);
         shortcutFeatureKeys.add(Settings.Secure.ACCESSIBILITY_SHORTCUT_TARGET_SERVICE);
-        mSettingsContentObserver = new SettingsContentObserver(mHandler, shortcutFeatureKeys) {
-            @Override
-            public void onChange(boolean selfChange, Uri uri) {
-                onContentChanged();
-            }
-        };
+        mSettingsContentObserver = new AccessibilitySettingsContentObserver(mHandler);
+        mSettingsContentObserver.registerKeysToObserverCallback(shortcutFeatureKeys,
+                key -> onContentChanged());
     }
 
     @Override
diff --git a/src/com/android/settings/accessibility/AccessibilitySettingsContentObserver.java b/src/com/android/settings/accessibility/AccessibilitySettingsContentObserver.java
new file mode 100644
index 0000000..d2ca754
--- /dev/null
+++ b/src/com/android/settings/accessibility/AccessibilitySettingsContentObserver.java
@@ -0,0 +1,132 @@
+/*
+ * 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.accessibility;
+
+import android.content.ContentResolver;
+import android.database.ContentObserver;
+import android.net.Uri;
+import android.os.Handler;
+import android.provider.Settings;
+import android.util.Log;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+class AccessibilitySettingsContentObserver extends ContentObserver {
+
+    private static final String TAG = "AccessibilitySettingsContentObserver";
+
+    public interface ContentObserverCallback {
+        void onChange(String key);
+    }
+
+    // Key: Preference key's uri, Value: Preference key
+    private final Map<Uri, String> mUriToKey = new HashMap<>(2);
+
+    // Key: Collection of preference keys, Value: onChange callback for keys
+    private final Map<List<String>, ContentObserverCallback> mUrisToCallback = new HashMap<>();
+
+    AccessibilitySettingsContentObserver(Handler handler) {
+        super(handler);
+
+        // default key to be observed
+        addDefaultKeysToMap();
+    }
+
+    public void register(ContentResolver contentResolver) {
+        for (Uri uri : mUriToKey.keySet()) {
+            contentResolver.registerContentObserver(uri, false, this);
+        }
+    }
+
+    public void unregister(ContentResolver contentResolver) {
+        contentResolver.unregisterContentObserver(this);
+    }
+
+    private void addDefaultKeysToMap() {
+        addKeyToMap(Settings.Secure.ACCESSIBILITY_ENABLED);
+        addKeyToMap(Settings.Secure.ENABLED_ACCESSIBILITY_SERVICES);
+    }
+
+    private boolean isDefaultKey(String key) {
+        return Settings.Secure.ACCESSIBILITY_ENABLED.equals(key)
+                || Settings.Secure.ENABLED_ACCESSIBILITY_SERVICES.equals(key);
+    }
+
+    private void addKeyToMap(String key) {
+        mUriToKey.put(Settings.Secure.getUriFor(key), key);
+    }
+
+    /**
+     * {@link ContentObserverCallback} is added to {@link ContentObserver} to handle the
+     * onChange event triggered by the key collection of {@code keysToObserve} and the default
+     * keys.
+     *
+     * Note: The following key are default to be observed.
+     *      {@link Settings.Secure.ACCESSIBILITY_ENABLED}
+     *      {@link Settings.Secure.ENABLED_ACCESSIBILITY_SERVICES}
+     *
+     * @param keysToObserve A collection of keys which are going to be observed.
+     * @param observerCallback A callback which is used to handle the onChange event triggered
+     *                         by the key collection of {@code keysToObserve}.
+     */
+    public void registerKeysToObserverCallback(List<String> keysToObserve,
+            ContentObserverCallback observerCallback) {
+
+        for (String key: keysToObserve) {
+            addKeyToMap(key);
+        }
+
+        mUrisToCallback.put(keysToObserve, observerCallback);
+    }
+
+    /**
+     * {@link ContentObserverCallback} is added to {@link ContentObserver} to handle the
+     * onChange event triggered by the default keys.
+     *
+     * Note: The following key are default to be observed.
+     *      {@link Settings.Secure.ACCESSIBILITY_ENABLED}
+     *      {@link Settings.Secure.ENABLED_ACCESSIBILITY_SERVICES}
+     *
+     * @param observerCallback A callback which is used to handle the onChange event triggered
+     *      *                         by the key collection of {@code keysToObserve}.
+     */
+    public void registerObserverCallback(ContentObserverCallback observerCallback) {
+        mUrisToCallback.put(Collections.emptyList(), observerCallback);
+    }
+
+    @Override
+    public final void onChange(boolean selfChange, Uri uri) {
+
+        final String key = mUriToKey.get(uri);
+
+        if (key == null) {
+            Log.w(TAG, "AccessibilitySettingsContentObserver can not find the key for "
+                    + "uri: " + uri);
+            return;
+        }
+
+        for (List<String> keys : mUrisToCallback.keySet()) {
+            final boolean isDefaultKey = isDefaultKey(key);
+            if (isDefaultKey || keys.contains(key)) {
+                mUrisToCallback.get(keys).onChange(key);
+            }
+        }
+    }
+}
diff --git a/src/com/android/settings/accessibility/AccessibilityShortcutPreferenceFragment.java b/src/com/android/settings/accessibility/AccessibilityShortcutPreferenceFragment.java
index 22f037b..115f44f 100644
--- a/src/com/android/settings/accessibility/AccessibilityShortcutPreferenceFragment.java
+++ b/src/com/android/settings/accessibility/AccessibilityShortcutPreferenceFragment.java
@@ -25,7 +25,6 @@
 import android.content.Context;
 import android.content.DialogInterface;
 import android.icu.text.CaseMap;
-import android.net.Uri;
 import android.os.Bundle;
 import android.os.Handler;
 import android.provider.Settings;
@@ -64,7 +63,7 @@
     protected ShortcutPreference mShortcutPreference;
     private AccessibilityManager.TouchExplorationStateChangeListener
             mTouchExplorationStateChangeListener;
-    private SettingsContentObserver mSettingsContentObserver;
+    private AccessibilitySettingsContentObserver mSettingsContentObserver;
     private CheckBox mSoftwareTypeCheckBox;
     private CheckBox mHardwareTypeCheckBox;
 
@@ -98,13 +97,11 @@
         final List<String> shortcutFeatureKeys = new ArrayList<>();
         shortcutFeatureKeys.add(Settings.Secure.ACCESSIBILITY_BUTTON_TARGETS);
         shortcutFeatureKeys.add(Settings.Secure.ACCESSIBILITY_SHORTCUT_TARGET_SERVICE);
-        mSettingsContentObserver = new SettingsContentObserver(new Handler(), shortcutFeatureKeys) {
-            @Override
-            public void onChange(boolean selfChange, Uri uri) {
-                updateShortcutPreferenceData();
-                updateShortcutPreference();
-            }
-        };
+        mSettingsContentObserver = new AccessibilitySettingsContentObserver(new Handler());
+        mSettingsContentObserver.registerKeysToObserverCallback(shortcutFeatureKeys, key -> {
+            updateShortcutPreferenceData();
+            updateShortcutPreference();
+        });
     }
 
     @Override
diff --git a/src/com/android/settings/accessibility/MagnificationFollowTypingPreferenceController.java b/src/com/android/settings/accessibility/MagnificationFollowTypingPreferenceController.java
index 8757fdf..a758276 100644
--- a/src/com/android/settings/accessibility/MagnificationFollowTypingPreferenceController.java
+++ b/src/com/android/settings/accessibility/MagnificationFollowTypingPreferenceController.java
@@ -35,6 +35,8 @@
 public class MagnificationFollowTypingPreferenceController extends TogglePreferenceController
         implements LifecycleObserver {
 
+    private static final String TAG =
+            MagnificationFollowTypingPreferenceController.class.getSimpleName();
     static final String PREF_KEY = "magnification_follow_typing";
 
     private SwitchPreference mFollowTypingPreference;
@@ -75,6 +77,14 @@
     // TODO(b/186731461): Remove it when this controller is used in DashBoardFragment only.
     @OnLifecycleEvent(Lifecycle.Event.ON_RESUME)
     void onResume() {
+        updateState();
+    }
+
+    /**
+     * Updates the state of preference components which has been displayed by
+     * {@link MagnificationFollowTypingPreferenceController#displayPreference}.
+     */
+    void updateState() {
         updateState(mFollowTypingPreference);
     }
 }
diff --git a/src/com/android/settings/accessibility/SettingsContentObserver.java b/src/com/android/settings/accessibility/SettingsContentObserver.java
deleted file mode 100644
index de67f6c..0000000
--- a/src/com/android/settings/accessibility/SettingsContentObserver.java
+++ /dev/null
@@ -1,55 +0,0 @@
-/*
- * Copyright (C) 2013 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.accessibility;
-
-import android.content.ContentResolver;
-import android.database.ContentObserver;
-import android.net.Uri;
-import android.os.Handler;
-import android.provider.Settings;
-
-import java.util.ArrayList;
-import java.util.List;
-
-abstract class SettingsContentObserver extends ContentObserver {
-    private final List<String> mKeysToObserve = new ArrayList<>(2);
-
-    public SettingsContentObserver(Handler handler) {
-        super(handler);
-        mKeysToObserve.add(Settings.Secure.ACCESSIBILITY_ENABLED);
-        mKeysToObserve.add(Settings.Secure.ENABLED_ACCESSIBILITY_SERVICES);
-    }
-
-    public SettingsContentObserver(Handler handler, List<String> keysToObserve) {
-        this(handler);
-        mKeysToObserve.addAll(keysToObserve);
-    }
-
-    public void register(ContentResolver contentResolver) {
-        for (int i = 0; i < mKeysToObserve.size(); i++) {
-            contentResolver.registerContentObserver(
-                    Settings.Secure.getUriFor(mKeysToObserve.get(i)), false, this);
-        }
-    }
-
-    public void unregister(ContentResolver contentResolver) {
-        contentResolver.unregisterContentObserver(this);
-    }
-
-    @Override
-    public abstract void onChange(boolean selfChange, Uri uri);
-}
diff --git a/src/com/android/settings/accessibility/ToggleAccessibilityServicePreferenceFragment.java b/src/com/android/settings/accessibility/ToggleAccessibilityServicePreferenceFragment.java
index 04b5347..0632d3f 100644
--- a/src/com/android/settings/accessibility/ToggleAccessibilityServicePreferenceFragment.java
+++ b/src/com/android/settings/accessibility/ToggleAccessibilityServicePreferenceFragment.java
@@ -35,7 +35,6 @@
 import android.content.pm.ServiceInfo;
 import android.net.Uri;
 import android.os.Bundle;
-import android.os.Handler;
 import android.os.SystemClock;
 import android.text.TextUtils;
 import android.util.Log;
@@ -65,15 +64,7 @@
 
     private static final String EMPTY_STRING = "";
 
-    private final SettingsContentObserver mSettingsContentObserver =
-            new SettingsContentObserver(new Handler()) {
-                @Override
-                public void onChange(boolean selfChange, Uri uri) {
-                    updateSwitchBarToggleSwitch();
-                }
-            };
-
-    private Dialog mDialog;
+    private Dialog mWarningDialog;
     private BroadcastReceiver mPackageRemovedReceiver;
     private boolean mDisabledStateLogged = false;
     private long mStartTimeMillsForLogging = 0;
@@ -109,6 +100,13 @@
     }
 
     @Override
+    protected void registerKeysToObserverCallback(
+            AccessibilitySettingsContentObserver contentObserver) {
+        super.registerKeysToObserverCallback(contentObserver);
+        contentObserver.registerObserverCallback(key -> updateSwitchBarToggleSwitch());
+    }
+
+    @Override
     public void onStart() {
         super.onStart();
         final AccessibilityServiceInfo serviceInfo = getAccessibilityServiceInfo();
@@ -123,7 +121,11 @@
     public void onResume() {
         super.onResume();
         updateSwitchBarToggleSwitch();
-        mSettingsContentObserver.register(getContentResolver());
+    }
+
+    @Override
+    public void onPause() {
+        super.onPause();
     }
 
     @Override
@@ -172,7 +174,7 @@
                 if (info == null) {
                     return null;
                 }
-                mDialog = AccessibilityServiceWarning
+                mWarningDialog = AccessibilityServiceWarning
                         .createCapabilitiesDialog(getPrefContext(), info,
                                 this::onDialogButtonFromEnableToggleClicked,
                                 this::onDialogButtonFromUninstallClicked);
@@ -183,7 +185,7 @@
                 if (info == null) {
                     return null;
                 }
-                mDialog = AccessibilityServiceWarning
+                mWarningDialog = AccessibilityServiceWarning
                         .createCapabilitiesDialog(getPrefContext(), info,
                                 this::onDialogButtonFromShortcutToggleClicked,
                                 this::onDialogButtonFromUninstallClicked);
@@ -194,7 +196,7 @@
                 if (info == null) {
                     return null;
                 }
-                mDialog = AccessibilityServiceWarning
+                mWarningDialog = AccessibilityServiceWarning
                         .createCapabilitiesDialog(getPrefContext(), info,
                                 this::onDialogButtonFromShortcutClicked,
                                 this::onDialogButtonFromUninstallClicked);
@@ -205,16 +207,16 @@
                 if (info == null) {
                     return null;
                 }
-                mDialog = AccessibilityServiceWarning
+                mWarningDialog = AccessibilityServiceWarning
                         .createDisableDialog(getPrefContext(), info,
                                 this::onDialogButtonFromDisableToggleClicked);
                 break;
             }
             default: {
-                mDialog = super.onCreateDialog(dialogId);
+                mWarningDialog = super.onCreateDialog(dialogId);
             }
         }
-        return mDialog;
+        return mWarningDialog;
     }
 
     @Override
@@ -402,7 +404,7 @@
     }
 
     private void onDialogButtonFromUninstallClicked() {
-        mDialog.dismiss();
+        mWarningDialog.dismiss();
         final Intent uninstallIntent = createUninstallPackageActivityIntent();
         if (uninstallIntent == null) {
             return;
@@ -436,12 +438,12 @@
             mIsDialogShown.set(false);
             showPopupDialog(DialogEnums.LAUNCH_ACCESSIBILITY_TUTORIAL);
         }
-        mDialog.dismiss();
+        mWarningDialog.dismiss();
     }
 
     private void onDenyButtonFromEnableToggleClicked() {
         handleConfirmServiceEnabled(/* confirmed= */ false);
-        mDialog.dismiss();
+        mWarningDialog.dismiss();
     }
 
     void onDialogButtonFromShortcutToggleClicked(View view) {
@@ -465,7 +467,7 @@
         mIsDialogShown.set(false);
         showPopupDialog(DialogEnums.LAUNCH_ACCESSIBILITY_TUTORIAL);
 
-        mDialog.dismiss();
+        mWarningDialog.dismiss();
 
         mShortcutPreference.setSummary(getShortcutTypeSummary(getPrefContext()));
     }
@@ -473,7 +475,7 @@
     private void onDenyButtonFromShortcutToggleClicked() {
         mShortcutPreference.setChecked(false);
 
-        mDialog.dismiss();
+        mWarningDialog.dismiss();
     }
 
     void onDialogButtonFromShortcutClicked(View view) {
@@ -491,11 +493,11 @@
         mIsDialogShown.set(false);
         showPopupDialog(DialogEnums.EDIT_SHORTCUT);
 
-        mDialog.dismiss();
+        mWarningDialog.dismiss();
     }
 
     private void onDenyButtonFromShortcutClicked() {
-        mDialog.dismiss();
+        mWarningDialog.dismiss();
     }
 
     private boolean onPreferenceClick(boolean isChecked) {
diff --git a/src/com/android/settings/accessibility/ToggleColorInversionPreferenceFragment.java b/src/com/android/settings/accessibility/ToggleColorInversionPreferenceFragment.java
index 419514f..e65c9c5 100644
--- a/src/com/android/settings/accessibility/ToggleColorInversionPreferenceFragment.java
+++ b/src/com/android/settings/accessibility/ToggleColorInversionPreferenceFragment.java
@@ -25,7 +25,6 @@
 import android.content.ContentResolver;
 import android.net.Uri;
 import android.os.Bundle;
-import android.os.Handler;
 import android.provider.Settings;
 import android.view.LayoutInflater;
 import android.view.View;
@@ -41,8 +40,6 @@
 public class ToggleColorInversionPreferenceFragment extends ToggleFeaturePreferenceFragment {
 
     private static final String ENABLED = Settings.Secure.ACCESSIBILITY_DISPLAY_INVERSION_ENABLED;
-    private final Handler mHandler = new Handler();
-    private SettingsContentObserver mSettingsContentObserver;
 
     @Override
     public int getMetricsCategory() {
@@ -86,20 +83,22 @@
                 .authority(getPrefContext().getPackageName())
                 .appendPath(String.valueOf(R.raw.accessibility_color_inversion_banner))
                 .build();
-        final List<String> enableServiceFeatureKeys = new ArrayList<>(/* initialCapacity= */ 1);
-        enableServiceFeatureKeys.add(ENABLED);
-        mSettingsContentObserver = new SettingsContentObserver(mHandler, enableServiceFeatureKeys) {
-            @Override
-            public void onChange(boolean selfChange, Uri uri) {
-                updateSwitchBarToggleSwitch();
-            }
-        };
-
         final View view = super.onCreateView(inflater, container, savedInstanceState);
         updateFooterPreference();
         return view;
     }
 
+    @Override
+    protected void registerKeysToObserverCallback(
+            AccessibilitySettingsContentObserver contentObserver) {
+        super.registerKeysToObserverCallback(contentObserver);
+
+        final List<String> enableServiceFeatureKeys = new ArrayList<>(/* initialCapacity= */ 1);
+        enableServiceFeatureKeys.add(ENABLED);
+        contentObserver.registerKeysToObserverCallback(enableServiceFeatureKeys,
+                key -> updateSwitchBarToggleSwitch());
+    }
+
     private void updateFooterPreference() {
         final String title = getPrefContext().getString(
                 R.string.accessibility_color_inversion_about_title);
@@ -114,12 +113,10 @@
     public void onResume() {
         super.onResume();
         updateSwitchBarToggleSwitch();
-        mSettingsContentObserver.register(getContentResolver());
     }
 
     @Override
     public void onPause() {
-        mSettingsContentObserver.unregister(getContentResolver());
         super.onPause();
     }
 
diff --git a/src/com/android/settings/accessibility/ToggleDaltonizerPreferenceFragment.java b/src/com/android/settings/accessibility/ToggleDaltonizerPreferenceFragment.java
index c9449d24..f0a4f0a 100644
--- a/src/com/android/settings/accessibility/ToggleDaltonizerPreferenceFragment.java
+++ b/src/com/android/settings/accessibility/ToggleDaltonizerPreferenceFragment.java
@@ -24,9 +24,7 @@
 import android.app.settings.SettingsEnums;
 import android.content.Context;
 import android.content.res.Resources;
-import android.net.Uri;
 import android.os.Bundle;
-import android.os.Handler;
 import android.provider.Settings;
 import android.view.LayoutInflater;
 import android.view.View;
@@ -53,8 +51,6 @@
     private static final String KEY_PREVIEW = "daltonizer_preview";
     private static final String KEY_CATEGORY_MODE = "daltonizer_mode_category";
     private static final List<AbstractPreferenceController> sControllers = new ArrayList<>();
-    private final Handler mHandler = new Handler();
-    private SettingsContentObserver mSettingsContentObserver;
 
     private static List<AbstractPreferenceController> buildPreferenceControllers(Context context,
             Lifecycle lifecycle) {
@@ -84,20 +80,22 @@
         mComponentName = DALTONIZER_COMPONENT_NAME;
         mPackageName = getText(R.string.accessibility_display_daltonizer_preference_title);
         mHtmlDescription = getText(R.string.accessibility_display_daltonizer_preference_subtitle);
-        final List<String> enableServiceFeatureKeys = new ArrayList<>(/* initialCapacity= */ 1);
-        enableServiceFeatureKeys.add(ENABLED);
-        mSettingsContentObserver = new SettingsContentObserver(mHandler, enableServiceFeatureKeys) {
-            @Override
-            public void onChange(boolean selfChange, Uri uri) {
-                updateSwitchBarToggleSwitch();
-            }
-        };
-
         final View view = super.onCreateView(inflater, container, savedInstanceState);
         updateFooterPreference();
         return view;
     }
 
+    @Override
+    protected void registerKeysToObserverCallback(
+            AccessibilitySettingsContentObserver contentObserver) {
+        super.registerKeysToObserverCallback(contentObserver);
+
+        final List<String> enableServiceFeatureKeys = new ArrayList<>(/* initialCapacity= */ 1);
+        enableServiceFeatureKeys.add(ENABLED);
+        contentObserver.registerKeysToObserverCallback(enableServiceFeatureKeys,
+                key -> updateSwitchBarToggleSwitch());
+    }
+
     private void updateFooterPreference() {
         final String title = getPrefContext()
                 .getString(R.string.accessibility_daltonizer_about_title);
@@ -123,8 +121,6 @@
     public void onResume() {
         super.onResume();
         updateSwitchBarToggleSwitch();
-        mSettingsContentObserver.register(getContentResolver());
-
         for (AbstractPreferenceController controller :
                 buildPreferenceControllers(getPrefContext(), getSettingsLifecycle())) {
             ((DaltonizerRadioButtonPreferenceController) controller).setOnChangeListener(this);
@@ -135,7 +131,6 @@
 
     @Override
     public void onPause() {
-        mSettingsContentObserver.unregister(getContentResolver());
         for (AbstractPreferenceController controller :
                 buildPreferenceControllers(getPrefContext(), getSettingsLifecycle())) {
             ((DaltonizerRadioButtonPreferenceController) controller).setOnChangeListener(null);
diff --git a/src/com/android/settings/accessibility/ToggleFeaturePreferenceFragment.java b/src/com/android/settings/accessibility/ToggleFeaturePreferenceFragment.java
index 233b7ee..cba5d83 100644
--- a/src/com/android/settings/accessibility/ToggleFeaturePreferenceFragment.java
+++ b/src/com/android/settings/accessibility/ToggleFeaturePreferenceFragment.java
@@ -99,7 +99,7 @@
     protected static final String KEY_ANIMATED_IMAGE = "animated_image";
 
     private TouchExplorationStateChangeListener mTouchExplorationStateChangeListener;
-    private SettingsContentObserver mSettingsContentObserver;
+    private AccessibilitySettingsContentObserver mSettingsContentObserver;
 
     private CheckBox mSoftwareTypeCheckBox;
     private CheckBox mHardwareTypeCheckBox;
@@ -143,17 +143,21 @@
             setPreferenceScreen(preferenceScreen);
         }
 
-        final List<String> shortcutFeatureKeys = getFeatureSettingsKeys();
-        mSettingsContentObserver = new SettingsContentObserver(new Handler(), shortcutFeatureKeys) {
-            @Override
-            public void onChange(boolean selfChange, Uri uri) {
-                updateShortcutPreferenceData();
-                updateShortcutPreference();
-            }
-        };
+        mSettingsContentObserver = new AccessibilitySettingsContentObserver(new Handler());
+        registerKeysToObserverCallback(mSettingsContentObserver);
     }
 
-    protected List<String> getFeatureSettingsKeys() {
+    protected void registerKeysToObserverCallback(
+            AccessibilitySettingsContentObserver contentObserver) {
+        final List<String> shortcutFeatureKeys = getShortcutFeatureSettingsKeys();
+
+        contentObserver.registerKeysToObserverCallback(shortcutFeatureKeys, key -> {
+            updateShortcutPreferenceData();
+            updateShortcutPreference();
+        });
+    }
+
+    protected List<String> getShortcutFeatureSettingsKeys() {
         final List<String> shortcutFeatureKeys = new ArrayList<>();
         shortcutFeatureKeys.add(Settings.Secure.ACCESSIBILITY_BUTTON_TARGETS);
         shortcutFeatureKeys.add(Settings.Secure.ACCESSIBILITY_SHORTCUT_TARGET_SERVICE);
diff --git a/src/com/android/settings/accessibility/ToggleReduceBrightColorsPreferenceFragment.java b/src/com/android/settings/accessibility/ToggleReduceBrightColorsPreferenceFragment.java
index 81bd45a..feb41a1 100644
--- a/src/com/android/settings/accessibility/ToggleReduceBrightColorsPreferenceFragment.java
+++ b/src/com/android/settings/accessibility/ToggleReduceBrightColorsPreferenceFragment.java
@@ -22,7 +22,6 @@
 import android.hardware.display.ColorDisplayManager;
 import android.net.Uri;
 import android.os.Bundle;
-import android.os.Handler;
 import android.provider.Settings;
 import android.view.LayoutInflater;
 import android.view.View;
@@ -50,8 +49,6 @@
     private static final String KEY_INTENSITY = "rbc_intensity";
     private static final String KEY_PERSIST = "rbc_persist";
 
-    private final Handler mHandler = new Handler();
-    private SettingsContentObserver mSettingsContentObserver;
     private ReduceBrightColorsIntensityPreferenceController mRbcIntensityPreferenceController;
     private ReduceBrightColorsPersistencePreferenceController mRbcPersistencePreferenceController;
     private ColorDisplayManager mColorDisplayManager;
@@ -67,20 +64,12 @@
         mComponentName = AccessibilityShortcutController.REDUCE_BRIGHT_COLORS_COMPONENT_NAME;
         mPackageName = getText(R.string.reduce_bright_colors_preference_title);
         mHtmlDescription = getText(R.string.reduce_bright_colors_preference_subtitle);
-        final List<String> enableServiceFeatureKeys = new ArrayList<>(/* initialCapacity= */ 1);
-        enableServiceFeatureKeys.add(REDUCE_BRIGHT_COLORS_ACTIVATED_KEY);
         mRbcIntensityPreferenceController =
                 new ReduceBrightColorsIntensityPreferenceController(getContext(), KEY_INTENSITY);
         mRbcPersistencePreferenceController =
                 new ReduceBrightColorsPersistencePreferenceController(getContext(), KEY_PERSIST);
         mRbcIntensityPreferenceController.displayPreference(getPreferenceScreen());
         mRbcPersistencePreferenceController.displayPreference(getPreferenceScreen());
-        mSettingsContentObserver = new SettingsContentObserver(mHandler, enableServiceFeatureKeys) {
-            @Override
-            public void onChange(boolean selfChange, Uri uri) {
-                updateSwitchBarToggleSwitch();
-            }
-        };
         mColorDisplayManager = getContext().getSystemService(ColorDisplayManager.class);
         final View view = super.onCreateView(inflater, container, savedInstanceState);
         // Parent sets the title when creating the view, so set it after calling super
@@ -90,6 +79,17 @@
         return view;
     }
 
+    @Override
+    protected void registerKeysToObserverCallback(
+            AccessibilitySettingsContentObserver contentObserver) {
+        super.registerKeysToObserverCallback(contentObserver);
+
+        final List<String> enableServiceFeatureKeys = new ArrayList<>(/* initialCapacity= */ 1);
+        enableServiceFeatureKeys.add(REDUCE_BRIGHT_COLORS_ACTIVATED_KEY);
+        contentObserver.registerKeysToObserverCallback(enableServiceFeatureKeys,
+                key -> updateSwitchBarToggleSwitch());
+    }
+
     private void updateGeneralCategoryOrder() {
         final PreferenceCategory generalCategory = findPreference(KEY_GENERAL_CATEGORY);
         final SeekBarPreference intensity = findPreference(KEY_INTENSITY);
@@ -117,12 +117,10 @@
     public void onResume() {
         super.onResume();
         updateSwitchBarToggleSwitch();
-        mSettingsContentObserver.register(getContentResolver());
     }
 
     @Override
     public void onPause() {
-        mSettingsContentObserver.unregister(getContentResolver());
         super.onPause();
     }
 
diff --git a/src/com/android/settings/accessibility/ToggleScreenMagnificationPreferenceFragment.java b/src/com/android/settings/accessibility/ToggleScreenMagnificationPreferenceFragment.java
index d1e9b56..5f76d5a 100644
--- a/src/com/android/settings/accessibility/ToggleScreenMagnificationPreferenceFragment.java
+++ b/src/com/android/settings/accessibility/ToggleScreenMagnificationPreferenceFragment.java
@@ -75,6 +75,9 @@
             new TextUtils.SimpleStringSplitter(COMPONENT_NAME_SEPARATOR);
 
     private DialogCreatable mDialogDelegate;
+    private MagnificationFollowTypingPreferenceController mFollowTypingPreferenceController;
+
+    protected SwitchPreference mFollowingTypingSwitchPreference;
 
     @Override
     public void onCreate(Bundle savedInstanceState) {
@@ -177,21 +180,20 @@
         getSettingsLifecycle().addObserver(magnificationModePreferenceController);
         magnificationModePreferenceController.displayPreference(getPreferenceScreen());
 
-        final SwitchPreference followingTypingSwitchPreference =
+        mFollowingTypingSwitchPreference =
                 new SwitchPreference(getPrefContext());
-        followingTypingSwitchPreference.setTitle(
+        mFollowingTypingSwitchPreference.setTitle(
                 R.string.accessibility_screen_magnification_follow_typing_title);
-        followingTypingSwitchPreference.setSummary(
+        mFollowingTypingSwitchPreference.setSummary(
                 R.string.accessibility_screen_magnification_follow_typing_summary);
-        followingTypingSwitchPreference.setKey(
+        mFollowingTypingSwitchPreference.setKey(
                 MagnificationFollowTypingPreferenceController.PREF_KEY);
-        generalCategory.addPreference(followingTypingSwitchPreference);
+        generalCategory.addPreference(mFollowingTypingSwitchPreference);
 
-        final MagnificationFollowTypingPreferenceController followTypingPreferenceController =
-                new MagnificationFollowTypingPreferenceController(getContext(),
-                        MagnificationFollowTypingPreferenceController.PREF_KEY);
-        getSettingsLifecycle().addObserver(followTypingPreferenceController);
-        followTypingPreferenceController.displayPreference(getPreferenceScreen());
+        mFollowTypingPreferenceController = new MagnificationFollowTypingPreferenceController(
+                getContext(), MagnificationFollowTypingPreferenceController.PREF_KEY);
+        getSettingsLifecycle().addObserver(mFollowTypingPreferenceController);
+        mFollowTypingPreferenceController.displayPreference(getPreferenceScreen());
     }
 
     @Override
@@ -293,8 +295,23 @@
     }
 
     @Override
-    protected List<String> getFeatureSettingsKeys() {
-        final List<String> shortcutKeys = super.getFeatureSettingsKeys();
+    protected void registerKeysToObserverCallback(
+            AccessibilitySettingsContentObserver contentObserver) {
+        super.registerKeysToObserverCallback(contentObserver);
+
+        final List<String> followingTypingKeys = new ArrayList<>();
+        followingTypingKeys.add(Settings.Secure.ACCESSIBILITY_MAGNIFICATION_FOLLOW_TYPING_ENABLED);
+        contentObserver.registerKeysToObserverCallback(followingTypingKeys,
+                key -> updateFollowTypingState());
+    }
+
+    private void updateFollowTypingState() {
+        mFollowTypingPreferenceController.updateState();
+    }
+
+    @Override
+    protected List<String> getShortcutFeatureSettingsKeys() {
+        final List<String> shortcutKeys = super.getShortcutFeatureSettingsKeys();
         shortcutKeys.add(Settings.Secure.ACCESSIBILITY_DISPLAY_MAGNIFICATION_ENABLED);
         return shortcutKeys;
     }
diff --git a/src/com/android/settings/accessibility/ToggleScreenMagnificationPreferenceFragmentForSetupWizard.java b/src/com/android/settings/accessibility/ToggleScreenMagnificationPreferenceFragmentForSetupWizard.java
index 799508b..d92fd51 100644
--- a/src/com/android/settings/accessibility/ToggleScreenMagnificationPreferenceFragmentForSetupWizard.java
+++ b/src/com/android/settings/accessibility/ToggleScreenMagnificationPreferenceFragmentForSetupWizard.java
@@ -44,9 +44,17 @@
         final Drawable icon = getContext().getDrawable(R.drawable.ic_accessibility_visibility);
         AccessibilitySetupWizardUtils.updateGlifPreferenceLayout(getContext(), layout, title,
                 description, icon);
+        hidePreferenceSettingComponents();
+    }
 
-        // Hide the setting from the vision settings.
+    /**
+     * Hide the magnification preference settings in the SuW's vision settings.
+     */
+    private void hidePreferenceSettingComponents() {
+        // Setting of magnification type
         mSettingsPreference.setVisible(false);
+        // Setting of following typing
+        mFollowingTypingSwitchPreference.setVisible(false);
     }
 
     @Override
diff --git a/src/com/android/settings/applications/AppLocaleUtil.java b/src/com/android/settings/applications/AppLocaleUtil.java
new file mode 100644
index 0000000..e795b01
--- /dev/null
+++ b/src/com/android/settings/applications/AppLocaleUtil.java
@@ -0,0 +1,68 @@
+/*
+ * 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.applications;
+
+import android.app.ActivityManager;
+import android.content.Context;
+import android.content.pm.PackageInfo;
+import android.content.pm.PackageManager;
+import android.util.Log;
+
+import com.android.settings.R;
+import com.android.settingslib.applications.ApplicationsState.AppEntry;
+
+/** This class provides methods that help dealing with per app locale. */
+public class AppLocaleUtil {
+    private static final String TAG = AppLocaleUtil.class.getSimpleName();
+
+    /**
+     * Decides the UI display of per app locale.
+     */
+    public static boolean canDisplayLocaleUi(Context context, AppEntry app) {
+        return !isDisallowedPackage(context, app.info.packageName)
+                && !isSignedWithPlatformKey(context, app.info.packageName)
+                && app.hasLauncherEntry;
+    }
+
+    private static boolean isDisallowedPackage(Context context, String packageName) {
+        final String[] disallowedPackages = context.getResources().getStringArray(
+                R.array.config_disallowed_app_localeChange_packages);
+        for (String disallowedPackage : disallowedPackages) {
+            if (packageName.equals(disallowedPackage)) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    private static boolean isSignedWithPlatformKey(Context context, String packageName) {
+        PackageInfo packageInfo = null;
+        PackageManager packageManager = context.getPackageManager();
+        ActivityManager activityManager = context.getSystemService(ActivityManager.class);
+        try {
+            packageInfo = packageManager.getPackageInfoAsUser(
+                    packageName, /* flags= */ 0,
+                    activityManager.getCurrentUser());
+        } catch (PackageManager.NameNotFoundException ex) {
+            Log.e(TAG, "package not found: " + packageName);
+        }
+        if (packageInfo == null) {
+            return false;
+        }
+        return packageInfo.applicationInfo.isSignedWithPlatformKey();
+    }
+}
diff --git a/src/com/android/settings/applications/AppStateLocaleBridge.java b/src/com/android/settings/applications/AppStateLocaleBridge.java
new file mode 100644
index 0000000..ebaf4ab
--- /dev/null
+++ b/src/com/android/settings/applications/AppStateLocaleBridge.java
@@ -0,0 +1,77 @@
+/*
+ * 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.applications;
+
+import android.content.Context;
+import android.util.Log;
+
+import com.android.settingslib.applications.ApplicationsState;
+import com.android.settingslib.applications.ApplicationsState.AppEntry;
+import com.android.settingslib.applications.ApplicationsState.AppFilter;
+
+import java.util.List;
+
+/**
+ * Creates a application filter to restrict UI display of applications.
+ * This is to avoid users from changing the per apps locale
+ * Also provides app filters that can use the info.
+ */
+public class AppStateLocaleBridge extends AppStateBaseBridge {
+    private static final String TAG = AppStateLocaleBridge.class.getSimpleName();
+
+    private final Context mContext;
+
+    public AppStateLocaleBridge(Context context, ApplicationsState appState,
+            Callback callback) {
+        super(appState, callback);
+        mContext = context;
+    }
+
+    @Override
+    protected void updateExtraInfo(AppEntry app, String packageName, int uid) {
+        app.extraInfo = AppLocaleUtil.canDisplayLocaleUi(mContext, app)
+                ? Boolean.TRUE : Boolean.FALSE;
+    }
+
+    @Override
+    protected void loadAllExtraInfo() {
+        final List<AppEntry> allApps = mAppSession.getAllApps();
+        for (int i = 0; i < allApps.size(); i++) {
+            AppEntry app = allApps.get(i);
+            app.extraInfo = AppLocaleUtil.canDisplayLocaleUi(mContext, app)
+                    ? Boolean.TRUE : Boolean.FALSE;
+        }
+    }
+
+    /** For the Settings which shows category of per app's locale. */
+    public static final AppFilter FILTER_APPS_LOCALE =
+            new AppFilter() {
+                @Override
+                public void init() {
+                }
+
+                @Override
+                public boolean filterApp(AppEntry entry) {
+                    if (entry.extraInfo == null) {
+                        Log.d(TAG, "No extra info.");
+                        return false;
+                    }
+                    return (Boolean) entry.extraInfo;
+                }
+            };
+
+
+}
diff --git a/src/com/android/settings/applications/appinfo/AppLocalePreferenceController.java b/src/com/android/settings/applications/appinfo/AppLocalePreferenceController.java
index f1e43ad..810d230 100644
--- a/src/com/android/settings/applications/appinfo/AppLocalePreferenceController.java
+++ b/src/com/android/settings/applications/appinfo/AppLocalePreferenceController.java
@@ -20,20 +20,23 @@
 import android.util.FeatureFlagUtils;
 
 import com.android.settings.SettingsPreferenceFragment;
+import com.android.settings.applications.AppLocaleUtil;
 
 /**
  * A controller to update current locale information of application.
  */
 public class AppLocalePreferenceController extends AppInfoPreferenceControllerBase {
+    private static final String TAG = AppLocalePreferenceController.class.getSimpleName();
+
     public AppLocalePreferenceController(Context context, String key) {
         super(context, key);
     }
 
     @Override
     public int getAvailabilityStatus() {
-        return FeatureFlagUtils
-                .isEnabled(mContext, FeatureFlagUtils.SETTINGS_APP_LANGUAGE_SELECTION)
-                ? AVAILABLE : CONDITIONALLY_UNAVAILABLE;
+        boolean isFeatureOn = FeatureFlagUtils
+                .isEnabled(mContext, FeatureFlagUtils.SETTINGS_APP_LANGUAGE_SELECTION);
+        return isFeatureOn && canDisplayLocaleUi() ? AVAILABLE : CONDITIONALLY_UNAVAILABLE;
     }
 
     @Override
@@ -45,4 +48,8 @@
     public CharSequence getSummary() {
         return AppLocaleDetails.getSummary(mContext, mParent.getAppEntry().info.packageName);
     }
+
+    boolean canDisplayLocaleUi() {
+        return AppLocaleUtil.canDisplayLocaleUi(mContext, mParent.getAppEntry());
+    }
 }
diff --git a/src/com/android/settings/applications/manageapplications/AppFilterRegistry.java b/src/com/android/settings/applications/manageapplications/AppFilterRegistry.java
index d1d4f62..6e67815 100644
--- a/src/com/android/settings/applications/manageapplications/AppFilterRegistry.java
+++ b/src/com/android/settings/applications/manageapplications/AppFilterRegistry.java
@@ -21,6 +21,7 @@
 import com.android.settings.R;
 import com.android.settings.applications.AppStateAlarmsAndRemindersBridge;
 import com.android.settings.applications.AppStateInstallAppsBridge;
+import com.android.settings.applications.AppStateLocaleBridge;
 import com.android.settings.applications.AppStateManageExternalStorageBridge;
 import com.android.settings.applications.AppStateMediaManagementAppsBridge;
 import com.android.settings.applications.AppStateNotificationBridge;
@@ -54,6 +55,7 @@
             FILTER_APPS_BLOCKED,
             FILTER_ALARMS_AND_REMINDERS,
             FILTER_APPS_MEDIA_MANAGEMENT,
+            FILTER_APPS_LOCALE,
     })
     @interface FilterType {
     }
@@ -79,14 +81,15 @@
     public static final int FILTER_MANAGE_EXTERNAL_STORAGE = 17;
     public static final int FILTER_ALARMS_AND_REMINDERS = 18;
     public static final int FILTER_APPS_MEDIA_MANAGEMENT = 19;
-    // Next id: 20. If you add an entry here, length of mFilters should be updated
+    public static final int FILTER_APPS_LOCALE = 20;
+    // Next id: 21. If you add an entry here, length of mFilters should be updated
 
     private static AppFilterRegistry sRegistry;
 
     private final AppFilterItem[] mFilters;
 
     private AppFilterRegistry() {
-        mFilters = new AppFilterItem[20];
+        mFilters = new AppFilterItem[21];
 
         // High power allowlist, on
         mFilters[FILTER_APPS_POWER_ALLOWLIST] = new AppFilterItem(
@@ -203,8 +206,16 @@
                 AppStateMediaManagementAppsBridge.FILTER_MEDIA_MANAGEMENT_APPS,
                 FILTER_APPS_MEDIA_MANAGEMENT,
                 R.string.media_management_apps_title);
+
+        // Apps that can configurate appication's locale.
+        mFilters[FILTER_APPS_LOCALE] = new AppFilterItem(
+                AppStateLocaleBridge.FILTER_APPS_LOCALE,
+            FILTER_APPS_LOCALE,
+                R.string.app_locale_picker_title);
     }
 
+
+
     public static AppFilterRegistry getInstance() {
         if (sRegistry == null) {
             sRegistry = new AppFilterRegistry();
@@ -235,6 +246,8 @@
                 return FILTER_ALARMS_AND_REMINDERS;
             case ManageApplications.LIST_TYPE_MEDIA_MANAGEMENT_APPS:
                 return FILTER_APPS_MEDIA_MANAGEMENT;
+            case ManageApplications.LIST_TYPE_APPS_LOCALE:
+                return FILTER_APPS_LOCALE;
             default:
                 return FILTER_APPS_ALL;
         }
diff --git a/src/com/android/settings/applications/manageapplications/ManageApplications.java b/src/com/android/settings/applications/manageapplications/ManageApplications.java
index d985482..01bc2f1 100644
--- a/src/com/android/settings/applications/manageapplications/ManageApplications.java
+++ b/src/com/android/settings/applications/manageapplications/ManageApplications.java
@@ -95,6 +95,7 @@
 import com.android.settings.applications.AppStateAppOpsBridge.PermissionState;
 import com.android.settings.applications.AppStateBaseBridge;
 import com.android.settings.applications.AppStateInstallAppsBridge;
+import com.android.settings.applications.AppStateLocaleBridge;
 import com.android.settings.applications.AppStateManageExternalStorageBridge;
 import com.android.settings.applications.AppStateMediaManagementAppsBridge;
 import com.android.settings.applications.AppStateNotificationBridge;
@@ -232,7 +233,7 @@
     public static final int LIST_MANAGE_EXTERNAL_STORAGE = 11;
     public static final int LIST_TYPE_ALARMS_AND_REMINDERS = 12;
     public static final int LIST_TYPE_MEDIA_MANAGEMENT_APPS = 13;
-    public static final int LIST_TYPE_APPS_LOCAL = 14;
+    public static final int LIST_TYPE_APPS_LOCALE = 14;
 
     // List types that should show instant apps.
     public static final Set<Integer> LIST_TYPES_WITH_INSTANT = new ArraySet<>(Arrays.asList(
@@ -321,7 +322,7 @@
             mNotificationBackend = new NotificationBackend();
             mSortOrder = R.id.sort_order_recent_notification;
         } else if (className.equals(AppLocaleDetails.class.getName())) {
-            mListType = LIST_TYPE_APPS_LOCAL;
+            mListType = LIST_TYPE_APPS_LOCALE;
         } else {
             mListType = LIST_TYPE_MAIN;
         }
@@ -504,7 +505,7 @@
                 return SettingsEnums.ALARMS_AND_REMINDERS;
             case LIST_TYPE_MEDIA_MANAGEMENT_APPS:
                 return SettingsEnums.MEDIA_MANAGEMENT_APPS;
-            case LIST_TYPE_APPS_LOCAL:
+            case LIST_TYPE_APPS_LOCALE:
                 return SettingsEnums.APPS_LOCALE_LIST;
             default:
                 return SettingsEnums.PAGE_UNKNOWN;
@@ -629,7 +630,7 @@
                 startAppInfoFragment(MediaManagementAppsDetails.class,
                         R.string.media_management_apps_title);
                 break;
-            case LIST_TYPE_APPS_LOCAL:
+            case LIST_TYPE_APPS_LOCALE:
                 startAppInfoFragment(AppLocaleDetails.class,
                         R.string.app_locale_picker_title);
                 break;
@@ -743,9 +744,9 @@
                 && mSortOrder != R.id.sort_order_size);
 
         mOptionsMenu.findItem(R.id.show_system).setVisible(!mShowSystem
-                && mListType != LIST_TYPE_HIGH_POWER);
+                && mListType != LIST_TYPE_HIGH_POWER && mListType != LIST_TYPE_APPS_LOCALE);
         mOptionsMenu.findItem(R.id.hide_system).setVisible(mShowSystem
-                && mListType != LIST_TYPE_HIGH_POWER);
+                && mListType != LIST_TYPE_HIGH_POWER && mListType != LIST_TYPE_APPS_LOCALE);
 
         mOptionsMenu.findItem(R.id.reset_app_preferences).setVisible(mListType == LIST_TYPE_MAIN);
 
@@ -1100,6 +1101,8 @@
                 mExtraInfoBridge = new AppStateAlarmsAndRemindersBridge(mContext, mState, this);
             } else if (mManageApplications.mListType == LIST_TYPE_MEDIA_MANAGEMENT_APPS) {
                 mExtraInfoBridge = new AppStateMediaManagementAppsBridge(mContext, mState, this);
+            } else if (mManageApplications.mListType == LIST_TYPE_APPS_LOCALE) {
+                mExtraInfoBridge = new AppStateLocaleBridge(mContext, mState, this);
             } else {
                 mExtraInfoBridge = null;
             }
@@ -1533,7 +1536,7 @@
                 case LIST_TYPE_MEDIA_MANAGEMENT_APPS:
                     holder.setSummary(MediaManagementAppsDetails.getSummary(mContext, entry));
                     break;
-                case LIST_TYPE_APPS_LOCAL:
+                case LIST_TYPE_APPS_LOCALE:
                     holder.setSummary(AppLocaleDetails
                             .getSummary(mContext, entry.info.packageName));
                     break;
diff --git a/src/com/android/settings/location/RecentLocationAccessPreferenceController.java b/src/com/android/settings/location/RecentLocationAccessPreferenceController.java
index a8a30b4..ba660ee 100644
--- a/src/com/android/settings/location/RecentLocationAccessPreferenceController.java
+++ b/src/com/android/settings/location/RecentLocationAccessPreferenceController.java
@@ -20,6 +20,7 @@
 import android.icu.text.RelativeDateTimeFormatter;
 import android.os.UserHandle;
 import android.os.UserManager;
+import android.provider.Settings;
 
 import androidx.annotation.VisibleForTesting;
 import androidx.preference.Preference;
@@ -85,11 +86,17 @@
     public void displayPreference(PreferenceScreen screen) {
         super.displayPreference(screen);
         mCategoryRecentLocationRequests = screen.findPreference(getPreferenceKey());
+    }
+
+    @Override
+    public void updateState(Preference preference) {
+        mCategoryRecentLocationRequests.removeAll();
         final Context prefContext = mCategoryRecentLocationRequests.getContext();
         final List<RecentAppOpsAccess.Access> recentLocationAccesses = new ArrayList<>();
         final UserManager userManager = UserManager.get(mContext);
-        for (RecentAppOpsAccess.Access access : mRecentLocationApps.getAppListSorted(
-                /* showSystemApps= */ false)) {
+        final boolean showSystem = Settings.Secure.getInt(mContext.getContentResolver(),
+                Settings.Secure.LOCATION_SHOW_SYSTEM_OPS, 0) == 1;
+        for (RecentAppOpsAccess.Access access : mRecentLocationApps.getAppListSorted(showSystem)) {
             if (isRequestMatchesProfileType(userManager, access, mType)) {
                 recentLocationAccesses.add(access);
                 if (recentLocationAccesses.size() == MAX_APPS) {
diff --git a/src/com/android/settings/location/RecentLocationAccessSeeAllFragment.java b/src/com/android/settings/location/RecentLocationAccessSeeAllFragment.java
index e27b28c..f7bf31a 100644
--- a/src/com/android/settings/location/RecentLocationAccessSeeAllFragment.java
+++ b/src/com/android/settings/location/RecentLocationAccessSeeAllFragment.java
@@ -17,6 +17,7 @@
 
 import android.content.Context;
 import android.os.Bundle;
+import android.provider.Settings;
 import android.view.Menu;
 import android.view.MenuInflater;
 import android.view.MenuItem;
@@ -36,7 +37,6 @@
 
     private static final int MENU_SHOW_SYSTEM = Menu.FIRST + 1;
     private static final int MENU_HIDE_SYSTEM = Menu.FIRST + 2;
-    private static final String EXTRA_SHOW_SYSTEM = "show_system";
 
     private boolean mShowSystem = false;
     private MenuItem mShowSystemMenu;
@@ -58,18 +58,8 @@
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
-        if (savedInstanceState != null) {
-            mShowSystem = savedInstanceState.getBoolean(EXTRA_SHOW_SYSTEM, mShowSystem);
-        }
-        if (mController != null) {
-            mController.setShowSystem(mShowSystem);
-        }
-    }
-
-    @Override
-    public void onSaveInstanceState(Bundle outState) {
-        super.onSaveInstanceState(outState);
-        outState.putBoolean(EXTRA_SHOW_SYSTEM, mShowSystem);
+        mShowSystem = Settings.Secure.getInt(getContentResolver(),
+                Settings.Secure.LOCATION_SHOW_SYSTEM_OPS, 0) == 1;
     }
 
     @Override
@@ -88,6 +78,8 @@
             case MENU_SHOW_SYSTEM:
             case MENU_HIDE_SYSTEM:
                 mShowSystem = menuItem.getItemId() == MENU_SHOW_SYSTEM;
+                Settings.Secure.putInt(getContentResolver(),
+                        Settings.Secure.LOCATION_SHOW_SYSTEM_OPS, mShowSystem ? 1 : 0);
                 updateMenu();
                 if (mController != null) {
                     mController.setShowSystem(mShowSystem);
diff --git a/src/com/android/settings/location/RecentLocationAccessSeeAllPreferenceController.java b/src/com/android/settings/location/RecentLocationAccessSeeAllPreferenceController.java
index bca4486..e3379c7 100644
--- a/src/com/android/settings/location/RecentLocationAccessSeeAllPreferenceController.java
+++ b/src/com/android/settings/location/RecentLocationAccessSeeAllPreferenceController.java
@@ -20,6 +20,7 @@
 
 import android.content.Context;
 import android.os.UserManager;
+import android.provider.Settings;
 
 import androidx.preference.Preference;
 import androidx.preference.PreferenceScreen;
@@ -43,6 +44,8 @@
 
     public RecentLocationAccessSeeAllPreferenceController(Context context, String key) {
         super(context, key);
+        mShowSystem = Settings.Secure.getInt(mContext.getContentResolver(),
+                Settings.Secure.LOCATION_SHOW_SYSTEM_OPS, 0) == 1;
         mRecentLocationAccesses = RecentAppOpsAccess.createForLocation(context);
     }
 
diff --git a/src/com/android/settings/location/RecentLocationRequestPreferenceController.java b/src/com/android/settings/location/RecentLocationRequestPreferenceController.java
index 812a440..a14e047 100644
--- a/src/com/android/settings/location/RecentLocationRequestPreferenceController.java
+++ b/src/com/android/settings/location/RecentLocationRequestPreferenceController.java
@@ -17,6 +17,7 @@
 import android.os.Bundle;
 import android.os.UserHandle;
 import android.os.UserManager;
+import android.provider.Settings;
 
 import androidx.annotation.VisibleForTesting;
 import androidx.preference.Preference;
@@ -83,8 +84,11 @@
         final Context prefContext = mCategoryRecentLocationRequests.getContext();
         final List<RecentLocationApps.Request> recentLocationRequests = new ArrayList<>();
         final UserManager userManager = UserManager.get(mContext);
+        final boolean showSystem = Settings.Secure.getInt(mContext.getContentResolver(),
+                Settings.Secure.LOCATION_SHOW_SYSTEM_OPS, 0) == 1;
+
         for (RecentLocationApps.Request request : mRecentLocationApps.getAppListSorted(
-                false /* systemApps */)) {
+                showSystem)) {
             if (isRequestMatchesProfileType(userManager, request, mType)) {
                 recentLocationRequests.add(request);
                 if (recentLocationRequests.size() == MAX_APPS) {
diff --git a/tests/robotests/src/com/android/settings/accessibility/AccessibilitySettingsContentObserverTest.java b/tests/robotests/src/com/android/settings/accessibility/AccessibilitySettingsContentObserverTest.java
new file mode 100644
index 0000000..e23d2d7
--- /dev/null
+++ b/tests/robotests/src/com/android/settings/accessibility/AccessibilitySettingsContentObserverTest.java
@@ -0,0 +1,160 @@
+/*
+ * 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.accessibility;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.spy;
+import static org.mockito.Mockito.verify;
+
+import android.content.ContentResolver;
+import android.content.Context;
+import android.database.ContentObserver;
+import android.os.Handler;
+import android.provider.Settings;
+
+import androidx.test.core.app.ApplicationProvider;
+
+import org.junit.After;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.robolectric.RobolectricTestRunner;
+import org.robolectric.shadow.api.Shadow;
+import org.robolectric.shadows.ShadowContentResolver;
+
+import java.util.Collection;
+import java.util.List;
+
+/** Test for {@link AccessibilitySettingsContentObserver}. */
+@RunWith(RobolectricTestRunner.class)
+public class AccessibilitySettingsContentObserverTest {
+
+    private static final String SPECIFIC_KEY_A_1 = "SPECIFIC_KEY_A_1";
+    private static final String SPECIFIC_KEY_A_2 = "SPECIFIC_KEY_A_2";
+    private static final String SPECIFIC_KEY_B_1 = "SPECIFIC_KEY_B_1";
+
+    private final Context mContext = ApplicationProvider.getApplicationContext();
+    private final AccessibilitySettingsContentObserver mObserver =
+            new AccessibilitySettingsContentObserver(new Handler());
+    private final AccessibilitySettingsContentObserver.ContentObserverCallback mObserverCallbackA =
+            spy(new TestableContentObserverCallback());
+    private final AccessibilitySettingsContentObserver.ContentObserverCallback mObserverCallbackB =
+            spy(new TestableContentObserverCallback());
+    private final ContentResolver mContentResolver = mContext.getContentResolver();
+
+    @Test
+    public void register_shouldRegisterContentObserverForDefaultKeys() {
+        mObserver.register(mContentResolver);
+
+        ShadowContentResolver shadowContentResolver = Shadow.extract(mContentResolver);
+        assertObserverToUri(shadowContentResolver,
+                Settings.Secure.ACCESSIBILITY_ENABLED, mObserver);
+        assertObserverToUri(shadowContentResolver,
+                Settings.Secure.ENABLED_ACCESSIBILITY_SERVICES, mObserver);
+    }
+
+    @Test
+    public void unregister_shouldUnregisterContentObserver() {
+        mObserver.register(mContentResolver);
+
+        mObserver.unregister(mContentResolver);
+
+        ShadowContentResolver shadowContentResolver = Shadow.extract(mContentResolver);
+        assertNotObserverToUri(shadowContentResolver, Settings.Secure.ACCESSIBILITY_ENABLED);
+        assertNotObserverToUri(shadowContentResolver,
+                Settings.Secure.ENABLED_ACCESSIBILITY_SERVICES);
+    }
+
+    @Test
+    public void register_addSpecificKeys_shouldRegisterContentObserverForSpecificAndDefaultKeys() {
+        mObserver.registerKeysToObserverCallback(List.of(SPECIFIC_KEY_A_1), mObserverCallbackA);
+
+        mObserver.register(mContentResolver);
+
+        ShadowContentResolver shadowContentResolver = Shadow.extract(mContentResolver);
+        assertObserverToUri(shadowContentResolver,
+                Settings.Secure.ACCESSIBILITY_ENABLED, mObserver);
+        assertObserverToUri(shadowContentResolver,
+                Settings.Secure.ENABLED_ACCESSIBILITY_SERVICES, mObserver);
+        assertObserverToUri(shadowContentResolver, SPECIFIC_KEY_A_1, mObserver);
+    }
+
+    @Test
+    public void onChange_shouldTriggerCallbackOnDefaultKey() {
+        mObserver.registerObserverCallback(mObserverCallbackA);
+        mObserver.register(mContentResolver);
+
+        mObserver.onChange(/* selfChange= */ false,
+                Settings.Secure.getUriFor(Settings.Secure.ACCESSIBILITY_ENABLED));
+
+        verify(mObserverCallbackA).onChange(Settings.Secure.ACCESSIBILITY_ENABLED);
+    }
+
+    @Test
+    public void onChange_registerSpecificKeys_shouldTriggerSpecificCallback() {
+        mObserver.registerKeysToObserverCallback(
+                List.of(SPECIFIC_KEY_A_1, SPECIFIC_KEY_A_2), mObserverCallbackA);
+        mObserver.register(mContentResolver);
+
+        mObserver.onChange(/* selfChange= */ false,
+                Settings.Secure.getUriFor(SPECIFIC_KEY_A_2));
+
+        verify(mObserverCallbackA).onChange(SPECIFIC_KEY_A_2);
+    }
+
+    @Test
+    public void onChange_registerSpecificKeys_withoutTriggerOtherCallback() {
+        mObserver.registerKeysToObserverCallback(
+                List.of(SPECIFIC_KEY_A_1, SPECIFIC_KEY_A_2), mObserverCallbackA);
+        mObserver.registerKeysToObserverCallback(
+                List.of(SPECIFIC_KEY_B_1), mObserverCallbackB);
+        mObserver.register(mContentResolver);
+
+        mObserver.onChange(/* selfChange= */ false,
+                Settings.Secure.getUriFor(SPECIFIC_KEY_B_1));
+
+        verify(mObserverCallbackA, never()).onChange(SPECIFIC_KEY_A_1);
+        verify(mObserverCallbackA, never()).onChange(SPECIFIC_KEY_A_2);
+        verify(mObserverCallbackA, never()).onChange(SPECIFIC_KEY_B_1);
+        verify(mObserverCallbackB).onChange(SPECIFIC_KEY_B_1);
+    }
+
+    @After
+    public void tearDown() {
+        mObserver.unregister(mContentResolver);
+    }
+
+    private void assertNotObserverToUri(ShadowContentResolver resolver, String key) {
+        assertThat(resolver.getContentObservers(Settings.Secure.getUriFor(key))).isEmpty();
+    }
+
+    private void assertObserverToUri(ShadowContentResolver resolver,
+            String key, ContentObserver observer) {
+        Collection<ContentObserver> observers =
+                resolver.getContentObservers(Settings.Secure.getUriFor(key));
+        assertThat(observers).contains(observer);
+    }
+
+    private static class TestableContentObserverCallback implements
+            AccessibilitySettingsContentObserver.ContentObserverCallback {
+        @Override
+        public void onChange(String key) {
+            // do nothing
+        }
+    }
+}
diff --git a/tests/robotests/src/com/android/settings/accessibility/AccessibilitySettingsTest.java b/tests/robotests/src/com/android/settings/accessibility/AccessibilitySettingsTest.java
index d1c59f7..5843265 100644
--- a/tests/robotests/src/com/android/settings/accessibility/AccessibilitySettingsTest.java
+++ b/tests/robotests/src/com/android/settings/accessibility/AccessibilitySettingsTest.java
@@ -281,10 +281,10 @@
         verify(mContentResolver).registerContentObserver(
                 eq(Settings.Secure.getUriFor(Settings.Secure.ACCESSIBILITY_BUTTON_TARGETS)),
                 anyBoolean(),
-                any(SettingsContentObserver.class));
+                any(AccessibilitySettingsContentObserver.class));
         verify(mContentResolver).registerContentObserver(eq(Settings.Secure.getUriFor(
                 Settings.Secure.ACCESSIBILITY_SHORTCUT_TARGET_SERVICE)), anyBoolean(),
-                any(SettingsContentObserver.class));
+                any(AccessibilitySettingsContentObserver.class));
         verify(mActivity, atLeast(1)).registerReceiver(any(PackageMonitor.class), captor.capture(),
                 isNull(), any());
         intentFilter = captor.getAllValues().get(/* first time */ 0);
@@ -301,7 +301,8 @@
 
         mFragment.onDestroy();
 
-        verify(mContentResolver).unregisterContentObserver(any(SettingsContentObserver.class));
+        verify(mContentResolver).unregisterContentObserver(
+                any(AccessibilitySettingsContentObserver.class));
         verify(mActivity).unregisterReceiver(any(PackageMonitor.class));
 
     }
diff --git a/tests/robotests/src/com/android/settings/accessibility/MagnificationFollowTypingPreferenceControllerTest.java b/tests/robotests/src/com/android/settings/accessibility/MagnificationFollowTypingPreferenceControllerTest.java
index ccb66ad..fd282a0 100644
--- a/tests/robotests/src/com/android/settings/accessibility/MagnificationFollowTypingPreferenceControllerTest.java
+++ b/tests/robotests/src/com/android/settings/accessibility/MagnificationFollowTypingPreferenceControllerTest.java
@@ -94,4 +94,15 @@
         assertThat(mController.isChecked()).isFalse();
         assertThat(mSwitchPreference.isChecked()).isFalse();
     }
+
+    @Test
+    public void updateState_disableFollowTyping_shouldReturnFalse() {
+        Settings.Secure.putInt(mContext.getContentResolver(), KEY_FOLLOW_TYPING, OFF);
+
+        mController.updateState();
+
+        verify(mSwitchPreference).setChecked(false);
+        assertThat(mController.isChecked()).isFalse();
+        assertThat(mSwitchPreference.isChecked()).isFalse();
+    }
 }
diff --git a/tests/robotests/src/com/android/settings/accessibility/ToggleFeaturePreferenceFragmentTest.java b/tests/robotests/src/com/android/settings/accessibility/ToggleFeaturePreferenceFragmentTest.java
index c47a793..4584b15 100644
--- a/tests/robotests/src/com/android/settings/accessibility/ToggleFeaturePreferenceFragmentTest.java
+++ b/tests/robotests/src/com/android/settings/accessibility/ToggleFeaturePreferenceFragmentTest.java
@@ -20,6 +20,8 @@
 
 import static com.google.common.truth.Truth.assertThat;
 
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.doReturn;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.spy;
@@ -27,6 +29,7 @@
 import static org.mockito.Mockito.when;
 
 import android.content.ComponentName;
+import android.content.ContentResolver;
 import android.content.Context;
 import android.content.DialogInterface;
 import android.os.Bundle;
@@ -75,12 +78,16 @@
             Settings.Secure.ACCESSIBILITY_SHORTCUT_TARGET_SERVICE;
 
     private TestToggleFeaturePreferenceFragment mFragment;
-    private PreferenceScreen mScreen;
-    private Context mContext = ApplicationProvider.getApplicationContext();
+    private final Context mContext = ApplicationProvider.getApplicationContext();
 
     @Mock(answer = Answers.RETURNS_DEEP_STUBS)
     private PreferenceManager mPreferenceManager;
 
+    @Mock
+    private FragmentActivity mActivity;
+    @Mock
+    private ContentResolver mContentResolver;
+
     @Before
     public void setUpTestFragment() {
         MockitoAnnotations.initMocks(this);
@@ -89,9 +96,11 @@
         when(mFragment.getPreferenceManager()).thenReturn(mPreferenceManager);
         when(mFragment.getPreferenceManager().getContext()).thenReturn(mContext);
         when(mFragment.getContext()).thenReturn(mContext);
-        mScreen = spy(new PreferenceScreen(mContext, null));
-        when(mScreen.getPreferenceManager()).thenReturn(mPreferenceManager);
-        doReturn(mScreen).when(mFragment).getPreferenceScreen();
+        when(mFragment.getActivity()).thenReturn(mActivity);
+        when(mActivity.getContentResolver()).thenReturn(mContentResolver);
+        final PreferenceScreen screen = spy(new PreferenceScreen(mContext, null));
+        when(screen.getPreferenceManager()).thenReturn(mPreferenceManager);
+        doReturn(screen).when(mFragment).getPreferenceScreen();
     }
 
     @Test
@@ -104,6 +113,25 @@
     }
 
     @Test
+    @Config(shadows = {ShadowFragment.class})
+    public void onResume_haveRegisterToSpecificUris() {
+        mFragment.onAttach(mContext);
+        mFragment.onCreate(Bundle.EMPTY);
+
+        mFragment.onResume();
+
+        verify(mContentResolver).registerContentObserver(
+                eq(Settings.Secure.getUriFor(Settings.Secure.ACCESSIBILITY_BUTTON_TARGETS)),
+                eq(false),
+                any(AccessibilitySettingsContentObserver.class));
+        verify(mContentResolver).registerContentObserver(
+                eq(Settings.Secure.getUriFor(
+                        Settings.Secure.ACCESSIBILITY_SHORTCUT_TARGET_SERVICE)),
+                eq(false),
+                any(AccessibilitySettingsContentObserver.class));
+    }
+
+    @Test
     public void updateShortcutPreferenceData_assignDefaultValueToVariable() {
         mFragment.mComponentName = PLACEHOLDER_COMPONENT_NAME;
 
diff --git a/tests/robotests/src/com/android/settings/accessibility/ToggleScreenMagnificationPreferenceFragmentTest.java b/tests/robotests/src/com/android/settings/accessibility/ToggleScreenMagnificationPreferenceFragmentTest.java
index 10495c5..8500e61 100644
--- a/tests/robotests/src/com/android/settings/accessibility/ToggleScreenMagnificationPreferenceFragmentTest.java
+++ b/tests/robotests/src/com/android/settings/accessibility/ToggleScreenMagnificationPreferenceFragmentTest.java
@@ -25,14 +25,15 @@
 
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyInt;
+import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.RETURNS_DEEP_STUBS;
-import static org.mockito.Mockito.doReturn;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.spy;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
 import android.content.ComponentName;
+import android.content.ContentResolver;
 import android.content.Context;
 import android.content.DialogInterface;
 import android.content.res.Resources;
@@ -63,8 +64,8 @@
 import org.junit.Ignore;
 import org.junit.Test;
 import org.junit.runner.RunWith;
+import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
-import org.robolectric.Robolectric;
 import org.robolectric.RobolectricTestRunner;
 import org.robolectric.annotation.Config;
 
@@ -96,17 +97,22 @@
     private Context mContext;
     private Resources mResources;
 
+    @Mock
+    private FragmentActivity mActivity;
+    @Mock
+    private ContentResolver mContentResolver;
+
     @Before
     public void setUpTestFragment() {
         MockitoAnnotations.initMocks(this);
 
         mContext = spy(ApplicationProvider.getApplicationContext());
-        final FragmentActivity activity = Robolectric.setupActivity(FragmentActivity.class);
         mFragment = spy(new TestToggleScreenMagnificationPreferenceFragment(mContext));
         mResources = spy(mContext.getResources());
         when(mContext.getResources()).thenReturn(mResources);
         when(mFragment.getContext().getResources()).thenReturn(mResources);
-        doReturn(activity).when(mFragment).getActivity();
+        when(mFragment.getActivity()).thenReturn(mActivity);
+        when(mActivity.getContentResolver()).thenReturn(mContentResolver);
     }
 
     @Ignore("Ignore it since a NPE is happened in ShadowWindowManagerGlobal. (Ref. b/214161063)")
@@ -143,6 +149,30 @@
     }
 
     @Test
+    @Config(shadows = {ShadowFragment.class})
+    public void onResume_haveRegisterToSpecificUris() {
+        mFragment.onAttach(mContext);
+        mFragment.onCreate(Bundle.EMPTY);
+
+        mFragment.onResume();
+
+        verify(mContentResolver).registerContentObserver(
+                eq(Settings.Secure.getUriFor(Settings.Secure.ACCESSIBILITY_BUTTON_TARGETS)),
+                eq(false),
+                any(AccessibilitySettingsContentObserver.class));
+        verify(mContentResolver).registerContentObserver(
+                eq(Settings.Secure.getUriFor(
+                        Settings.Secure.ACCESSIBILITY_SHORTCUT_TARGET_SERVICE)),
+                eq(false),
+                any(AccessibilitySettingsContentObserver.class));
+        verify(mContentResolver).registerContentObserver(
+                eq(Settings.Secure.getUriFor(
+                        Settings.Secure.ACCESSIBILITY_MAGNIFICATION_FOLLOW_TYPING_ENABLED)),
+                eq(false),
+                any(AccessibilitySettingsContentObserver.class));
+    }
+
+    @Test
     public void hasValueInSettings_putValue_hasValue() {
         setMagnificationTripleTapEnabled(/* enabled= */ true);
 
diff --git a/tests/robotests/src/com/android/settings/accounts/WorkModePreferenceControllerTest.java b/tests/robotests/src/com/android/settings/accounts/WorkModePreferenceControllerTest.java
index c7e571f..b5d1cc7 100644
--- a/tests/robotests/src/com/android/settings/accounts/WorkModePreferenceControllerTest.java
+++ b/tests/robotests/src/com/android/settings/accounts/WorkModePreferenceControllerTest.java
@@ -18,6 +18,7 @@
 import static com.google.common.truth.Truth.assertThat;
 
 import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyInt;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.spy;
 import static org.mockito.Mockito.verify;
@@ -32,7 +33,6 @@
 import com.android.settings.R;
 
 import org.junit.Before;
-import org.junit.Ignore;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.mockito.Mock;
@@ -106,10 +106,9 @@
     }
 
     @Test
-    @Ignore
     public void onStart_shouldRegisterReceiver() {
         mController.onStart();
-        verify(mContext).registerReceiver(eq(mController.mReceiver), any());
+        verify(mContext).registerReceiver(eq(mController.mReceiver), any(), anyInt());
     }
 
     @Test
diff --git a/tests/robotests/src/com/android/settings/location/LocationInjectedServicesPreferenceControllerTest.java b/tests/robotests/src/com/android/settings/location/LocationInjectedServicesPreferenceControllerTest.java
index ad928da..ae62724 100644
--- a/tests/robotests/src/com/android/settings/location/LocationInjectedServicesPreferenceControllerTest.java
+++ b/tests/robotests/src/com/android/settings/location/LocationInjectedServicesPreferenceControllerTest.java
@@ -43,7 +43,6 @@
 import com.android.settingslib.core.lifecycle.Lifecycle;
 
 import org.junit.Before;
-import org.junit.Ignore;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.mockito.Answers;
@@ -98,16 +97,15 @@
     }
 
     @Test
-    @Ignore
     public void onResume_shouldRegisterListener() {
         mController.onResume();
 
         verify(mContext).registerReceiver(eq(mController.mInjectedSettingsReceiver),
-                eq(mController.INTENT_FILTER_INJECTED_SETTING_CHANGED));
+                eq(mController.INTENT_FILTER_INJECTED_SETTING_CHANGED),
+                anyInt());
     }
 
     @Test
-    @Ignore
     public void onPause_shouldUnregisterListener() {
         mController.onResume();
         mController.onPause();
diff --git a/tests/robotests/src/com/android/settings/location/RecentLocationAccessPreferenceControllerTest.java b/tests/robotests/src/com/android/settings/location/RecentLocationAccessPreferenceControllerTest.java
index 52068c4..225f91b 100644
--- a/tests/robotests/src/com/android/settings/location/RecentLocationAccessPreferenceControllerTest.java
+++ b/tests/robotests/src/com/android/settings/location/RecentLocationAccessPreferenceControllerTest.java
@@ -19,9 +19,12 @@
 
 import static org.mockito.Mockito.doReturn;
 import static org.mockito.Mockito.spy;
+import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
 import android.content.Context;
+import android.os.UserHandle;
+import android.provider.Settings;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.widget.TextView;
@@ -34,12 +37,15 @@
 import com.android.settings.testutils.shadow.ShadowDeviceConfig;
 import com.android.settingslib.applications.RecentAppOpsAccess;
 
+import com.google.common.collect.ImmutableList;
+
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Ignore;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.mockito.Mock;
+import org.mockito.Mockito;
 import org.mockito.MockitoAnnotations;
 import org.robolectric.RobolectricTestRunner;
 import org.robolectric.RuntimeEnvironment;
@@ -107,4 +113,20 @@
                 mContext.getText(R.string.location_recent_location_access_view_details));
         assertThat(details.hasOnClickListeners()).isTrue();
     }
+
+    /** Verifies the title text, details text are correct, and the click listener is set. */
+    @Test
+    public void updateState_showSystemAccess() {
+        doReturn(ImmutableList.of(
+                new RecentAppOpsAccess.Access("app", UserHandle.CURRENT, null, "app", "", 0)))
+                .when(mRecentLocationApps).getAppListSorted(false);
+        doReturn(new ArrayList<>()).when(mRecentLocationApps).getAppListSorted(true);
+        mController.displayPreference(mScreen);
+        mController.updateState(mLayoutPreference);
+        verify(mLayoutPreference).addPreference(Mockito.any());
+
+        Settings.Secure.putInt(
+                mContext.getContentResolver(), Settings.Secure.LOCATION_SHOW_SYSTEM_OPS, 1);
+        verify(mLayoutPreference, Mockito.times(1)).addPreference(Mockito.any());
+    }
 }
diff --git a/tests/robotests/src/com/android/settings/location/RecentLocationRequestPreferenceControllerTest.java b/tests/robotests/src/com/android/settings/location/RecentLocationRequestPreferenceControllerTest.java
index 545a358..be778cb 100644
--- a/tests/robotests/src/com/android/settings/location/RecentLocationRequestPreferenceControllerTest.java
+++ b/tests/robotests/src/com/android/settings/location/RecentLocationRequestPreferenceControllerTest.java
@@ -26,6 +26,7 @@
 import android.content.Context;
 import android.graphics.drawable.Drawable;
 import android.os.UserHandle;
+import android.provider.Settings;
 
 import androidx.preference.PreferenceCategory;
 import androidx.preference.PreferenceScreen;
@@ -82,6 +83,25 @@
     }
 
     @Test
+    public void updateState_whenAppListMoreThanThree_showSystem() {
+        when(mController.mRecentLocationApps.getAppListSorted(false))
+                .thenReturn(createMockRequest(2));
+        when(mController.mRecentLocationApps.getAppListSorted(true))
+                .thenReturn(createMockRequest(3));
+
+        mController.displayPreference(mScreen);
+        verify(mCategory, times(2)).addPreference(any());
+
+        Settings.Secure.putInt(
+                mContext.getContentResolver(),
+                Settings.Secure.LOCATION_SHOW_SYSTEM_OPS,
+                1);
+
+        mController.displayPreference(mScreen);
+        verify(mCategory, times(5)).addPreference(any());
+    }
+
+    @Test
     public void updateState_workProfile_shouldShowOnlyWorkProfileApps() {
         final List<RecentLocationApps.Request> requests = createMockRequest(6);
         when(mController.mRecentLocationApps.getAppListSorted(false)).thenReturn(requests);
diff --git a/tests/robotests/src/com/android/settings/search/SearchFeatureProviderImplTest.java b/tests/robotests/src/com/android/settings/search/SearchFeatureProviderImplTest.java
index bcc6455..15a124d 100644
--- a/tests/robotests/src/com/android/settings/search/SearchFeatureProviderImplTest.java
+++ b/tests/robotests/src/com/android/settings/search/SearchFeatureProviderImplTest.java
@@ -68,7 +68,9 @@
         final Intent searchIntent = new Intent(Settings.ACTION_APP_SEARCH_SETTINGS)
                 .setPackage(mActivity.getString(R.string.config_settingsintelligence_package_name));
         final ResolveInfo info = new ResolveInfo();
-        info.activityInfo = new ActivityInfo();
+        final ActivityInfo activityInfo = new ActivityInfo();
+        activityInfo.packageName = "com.android.example";
+        info.activityInfo = activityInfo;
         mPackageManager.addResolveInfoForIntent(searchIntent, info);
 
         // Should not crash.
diff --git a/tests/unit/src/com/android/settings/applications/AppLocaleUtilTest.java b/tests/unit/src/com/android/settings/applications/AppLocaleUtilTest.java
new file mode 100644
index 0000000..22a055f
--- /dev/null
+++ b/tests/unit/src/com/android/settings/applications/AppLocaleUtilTest.java
@@ -0,0 +1,135 @@
+/*
+ * 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.applications;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static org.mockito.ArgumentMatchers.anyInt;
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.Mockito.spy;
+import static org.mockito.Mockito.when;
+
+import android.app.ActivityManager;
+import android.content.Context;
+import android.content.pm.ApplicationInfo;
+import android.content.pm.PackageInfo;
+import android.content.pm.PackageManager;
+import android.content.res.Resources;
+
+import androidx.test.core.app.ApplicationProvider;
+import androidx.test.ext.junit.runners.AndroidJUnit4;
+
+import com.android.settingslib.applications.ApplicationsState.AppEntry;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+
+@RunWith(AndroidJUnit4.class)
+public class AppLocaleUtilTest {
+    @Mock
+    private PackageManager mPackageManager;
+    @Mock
+    private ActivityManager mActivityManager;
+    @Mock
+    private AppEntry mEntry;
+    @Mock
+    private ApplicationInfo mApplicationInfo;
+    @Mock
+    private Resources mResources;
+
+    private Context mContext;
+    private String mDisallowedPackage = "com.disallowed.package";
+    private String mAallowedPackage = "com.allowed.package";
+
+    @Before
+    public void setUp() {
+        MockitoAnnotations.initMocks(this);
+        mContext = spy(ApplicationProvider.getApplicationContext());
+        when(mContext.getPackageManager()).thenReturn(mPackageManager);
+        when(mContext.getSystemService(ActivityManager.class)).thenReturn(mActivityManager);
+    }
+
+    @Test
+    public void isDisplayLocaleUi_showUI() throws PackageManager.NameNotFoundException {
+        setTestAppEntry(mAallowedPackage);
+        setDisallowedPackageName(mDisallowedPackage);
+        setApplicationInfo(/*no platform key*/false);
+        mEntry.hasLauncherEntry = true;
+
+        assertTrue(AppLocaleUtil.canDisplayLocaleUi(mContext, mEntry));
+    }
+
+    @Test
+    public void isDisplayLocaleUi_notShowUI_hasPlatformKey()
+            throws PackageManager.NameNotFoundException {
+        setTestAppEntry(mAallowedPackage);
+        setDisallowedPackageName(mDisallowedPackage);
+        setApplicationInfo(/*has platform key*/true);
+        mEntry.hasLauncherEntry = true;
+
+        assertFalse(AppLocaleUtil.canDisplayLocaleUi(mContext, mEntry));
+    }
+
+    @Test
+    public void isDisplayLocaleUi_notShowUI_noLauncherEntry()
+            throws PackageManager.NameNotFoundException {
+        setTestAppEntry(mAallowedPackage);
+        setDisallowedPackageName(mDisallowedPackage);
+        setApplicationInfo(/*no platform key*/false);
+        mEntry.hasLauncherEntry = false;
+
+        assertFalse(AppLocaleUtil.canDisplayLocaleUi(mContext, mEntry));
+    }
+
+    @Test
+    public void isDisplayLocaleUi_notShowUI_matchDisallowedPackageList()
+            throws PackageManager.NameNotFoundException {
+        setTestAppEntry(mDisallowedPackage);
+        setDisallowedPackageName(mDisallowedPackage);
+        setApplicationInfo(/*no platform key*/false);
+        mEntry.hasLauncherEntry = false;
+
+        assertFalse(AppLocaleUtil.canDisplayLocaleUi(mContext, mEntry));
+    }
+
+    private void setTestAppEntry(String packageName) {
+        mEntry.info = mApplicationInfo;
+        mApplicationInfo.packageName = packageName;
+    }
+
+    private void setDisallowedPackageName(String packageName) {
+        when(mContext.getResources()).thenReturn(mResources);
+        when(mResources.getStringArray(anyInt())).thenReturn(new String[]{packageName});
+    }
+
+    private void setApplicationInfo(boolean signedWithPlatformKey)
+            throws PackageManager.NameNotFoundException {
+        ApplicationInfo applicationInfo = new ApplicationInfo();
+        if (signedWithPlatformKey) {
+            applicationInfo.privateFlags = applicationInfo.privateFlags
+                    | ApplicationInfo.PRIVATE_FLAG_SIGNED_WITH_PLATFORM_KEY;
+        }
+
+        PackageInfo packageInfo = new PackageInfo();
+        packageInfo.applicationInfo = applicationInfo;
+        when(mPackageManager.getPackageInfoAsUser(anyString(), anyInt(), anyInt())).thenReturn(
+                packageInfo);
+    }
+}
diff --git a/tests/unit/src/com/android/settings/applications/appinfo/AppLocalePreferenceControllerTest.java b/tests/unit/src/com/android/settings/applications/appinfo/AppLocalePreferenceControllerTest.java
index d7e3f92..526b6cc 100644
--- a/tests/unit/src/com/android/settings/applications/appinfo/AppLocalePreferenceControllerTest.java
+++ b/tests/unit/src/com/android/settings/applications/appinfo/AppLocalePreferenceControllerTest.java
@@ -18,8 +18,6 @@
 
 import static com.google.common.truth.Truth.assertThat;
 
-import static org.mockito.Mockito.spy;
-
 import android.content.Context;
 import android.util.FeatureFlagUtils;
 
@@ -37,20 +35,27 @@
 public class AppLocalePreferenceControllerTest {
 
     private Context mContext;
+    private boolean mCanDisplayLocaleUi;
     private AppLocalePreferenceController mController;
 
     @Before
     public void setUp() {
         MockitoAnnotations.initMocks(this);
-        mContext = spy(ApplicationProvider.getApplicationContext());
+        mContext = ApplicationProvider.getApplicationContext();
 
-        mController = spy(new AppLocalePreferenceController(mContext, "test_key"));
+        mController = new AppLocalePreferenceController(mContext, "test_key") {
+            @Override
+            boolean canDisplayLocaleUi() {
+                return mCanDisplayLocaleUi;
+            }
+        };
         FeatureFlagUtils
                 .setEnabled(mContext, FeatureFlagUtils.SETTINGS_APP_LANGUAGE_SELECTION, true);
     }
 
     @Test
-    public void getAvailabilityStatus_featureFlagOff_shouldReturnUnavailable() {
+    public void getAvailabilityStatus_canShowUiButFeatureFlagOff_shouldReturnUnavailable() {
+        mCanDisplayLocaleUi = true;
         FeatureFlagUtils
                 .setEnabled(mContext, FeatureFlagUtils.SETTINGS_APP_LANGUAGE_SELECTION, false);
 
@@ -59,8 +64,28 @@
     }
 
     @Test
-    public void getAvailabilityStatus_featureFlagOn_shouldReturnAvailable() {
+    public void getAvailabilityStatus_canShowUiAndFeatureFlagOn_shouldReturnAvailable() {
+        mCanDisplayLocaleUi = true;
+
         assertThat(mController.getAvailabilityStatus())
                 .isEqualTo(BasePreferenceController.AVAILABLE);
     }
+
+    @Test
+    public void getAvailabilityStatus_featureFlagOnButCanNotShowUi_shouldReturnUnavailable() {
+        mCanDisplayLocaleUi = false;
+
+        assertThat(mController.getAvailabilityStatus())
+                .isEqualTo(BasePreferenceController.CONDITIONALLY_UNAVAILABLE);
+    }
+
+    @Test
+    public void getAvailabilityStatus_featureFlagOffAndCanNotShowUi_shouldReturnUnavailable() {
+        mCanDisplayLocaleUi = false;
+        FeatureFlagUtils
+                .setEnabled(mContext, FeatureFlagUtils.SETTINGS_APP_LANGUAGE_SELECTION, false);
+
+        assertThat(mController.getAvailabilityStatus())
+                .isEqualTo(BasePreferenceController.CONDITIONALLY_UNAVAILABLE);
+    }
 }