Merge "Update WebView implementation Dev Setting - new looks + descriptions."

src/com/android/settings/DevelopmentSettings.java

@@ -78,7 +78,7 @@ import android.view.View;
 import android.view.ViewGroup;
 import android.view.accessibility.AccessibilityManager;
 import android.webkit.IWebViewUpdateService;
-import android.webkit.WebViewProviderInfo;
+import android.webkit.WebViewFactory;
 import android.widget.Switch;
 import android.widget.Toast;
 
@@ -92,6 +92,7 @@ import com.android.settings.fuelgauge.InactiveApps;
 import com.android.settings.overlay.FeatureFactory;
 import com.android.settings.search.BaseSearchIndexProvider;
 import com.android.settings.search.Indexable;
+import com.android.settings.webview.WebViewAppPreferenceController;
 import com.android.settings.widget.SwitchBar;
 import com.android.settingslib.RestrictedLockUtils;
 import com.android.settingslib.RestrictedLockUtils.EnforcedAdmin;
@@ -126,7 +127,6 @@ public class DevelopmentSettings extends RestrictedSettingsFragment
     private static final String ENABLE_TERMINAL = "enable_terminal";
     private static final String KEEP_SCREEN_ON = "keep_screen_on";
     private static final String BT_HCI_SNOOP_LOG = "bt_hci_snoop_log";
-    private static final String WEBVIEW_PROVIDER_KEY = "select_webview_provider";
     private static final String WEBVIEW_MULTIPROCESS_KEY = "enable_webview_multiprocess";
     private static final String ENABLE_OEM_UNLOCK = "oem_unlock_enable";
     private static final String HDCP_CHECKING_KEY = "hdcp_checking";
@@ -230,6 +230,7 @@ public class DevelopmentSettings extends RestrictedSettingsFragment
 
     private static final int RESULT_DEBUG_APP = 1000;
     private static final int RESULT_MOCK_LOCATION_APP = 1001;
+    private static final int RESULT_WEBVIEW_APP = 1002;
 
     private static final String PERSISTENT_DATA_BLOCK_PROP = "ro.frp.pst";
     private static final String FLASH_LOCKED_PROP = "ro.boot.flash.locked";
@@ -310,8 +311,8 @@ public class DevelopmentSettings extends RestrictedSettingsFragment
     private ListPreference mAnimatorDurationScale;
     private ListPreference mOverlayDisplayDevices;
 
+    private WebViewAppPreferenceController mWebViewAppPrefController;
     private SwitchPreference mWebViewMultiprocess;
-    private ListPreference mWebViewProvider;
 
     private ListPreference mSimulateColorSpace;
 
@@ -371,8 +372,7 @@ public class DevelopmentSettings extends RestrictedSettingsFragment
         mWindowManager = IWindowManager.Stub.asInterface(ServiceManager.getService("window"));
         mBackupManager = IBackupManager.Stub.asInterface(
                 ServiceManager.getService(Context.BACKUP_SERVICE));
-        mWebViewUpdateService =
-                IWebViewUpdateService.Stub.asInterface(ServiceManager.getService("webviewupdate"));
+        mWebViewUpdateService = WebViewFactory.getUpdateService();
         mOemUnlockManager = (PersistentDataBlockManager) getActivity()
                 .getSystemService(Context.PERSISTENT_DATA_BLOCK_SERVICE);
         mTelephonyManager = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
@@ -384,6 +384,7 @@ public class DevelopmentSettings extends RestrictedSettingsFragment
 
         mBugReportController = new BugReportPreferenceController(getActivity());
         mBugReportInPowerController = new BugReportInPowerPreferenceController(getActivity());
+        mWebViewAppPrefController = new WebViewAppPreferenceController(getActivity());
 
         setIfOnlyAvailableForAdmins(true);
         if (isUiRestricted() || !Utils.isDeviceProvisioned(getActivity())) {
@@ -414,6 +415,7 @@ public class DevelopmentSettings extends RestrictedSettingsFragment
 
         mBugReportController.displayPreference(getPreferenceScreen());
         mBugReportInPowerController.displayPreference(getPreferenceScreen());
+        mWebViewAppPrefController.displayPreference(getPreferenceScreen());
 
         mKeepScreenOn = (RestrictedSwitchPreference) findAndInitSwitchPref(KEEP_SCREEN_ON);
         mBtHciSnoopLog = findAndInitSwitchPref(BT_HCI_SNOOP_LOG);
@@ -483,7 +485,6 @@ public class DevelopmentSettings extends RestrictedSettingsFragment
             mLogpersist = null;
         }
         mUsbConfiguration = addListPreference(USB_CONFIGURATION_KEY);
-        mWebViewProvider = addListPreference(WEBVIEW_PROVIDER_KEY);
         mWebViewMultiprocess = findAndInitSwitchPref(WEBVIEW_MULTIPROCESS_KEY);
         mBluetoothDisableAbsVolume = findAndInitSwitchPref(BLUETOOTH_DISABLE_ABSOLUTE_VOLUME_KEY);
 
@@ -544,7 +545,6 @@ public class DevelopmentSettings extends RestrictedSettingsFragment
             removePreference(KEY_COLOR_MODE);
             mColorModePreference = null;
         }
-        updateWebViewProviderOptions();
 
         mColorTemperaturePreference = (SwitchPreference) findPreference(COLOR_TEMPERATURE_KEY);
         if (getResources().getBoolean(R.bool.config_enableColorTemperature)) {
@@ -629,6 +629,7 @@ public class DevelopmentSettings extends RestrictedSettingsFragment
             pref.setEnabled(enabled && !mDisabledPrefs.contains(pref));
         }
         mBugReportInPowerController.enablePreference(enabled);
+        mWebViewAppPrefController.enablePreference(enabled);
         updateAllOptions();
     }
 
@@ -793,8 +794,8 @@ public class DevelopmentSettings extends RestrictedSettingsFragment
         updateSimulateColorSpace();
         updateUSBAudioOptions();
         updateForceResizableOptions();
+        mWebViewAppPrefController.updateState(null);
         updateWebViewMultiprocessOptions();
-        updateWebViewProviderOptions();
         updateOemUnlockOptions();
         if (mColorTemperaturePreference != null) {
             updateColorTemperature();
@@ -831,39 +832,6 @@ public class DevelopmentSettings extends RestrictedSettingsFragment
         pokeSystemProperties();
     }
 
-    private void updateWebViewProviderOptions() {
-        try {
-            WebViewProviderInfo[] providers = mWebViewUpdateService.getValidWebViewPackages();
-            if (providers == null) {
-                Log.e(TAG, "No WebView providers available");
-                return;
-            }
-            ArrayList<String> options = new ArrayList<String>();
-            ArrayList<String> values = new ArrayList<String>();
-            for (int n = 0; n < providers.length; n++) {
-                if (Utils.isPackageEnabled(getActivity(), providers[n].packageName)) {
-                    options.add(providers[n].description);
-                    values.add(providers[n].packageName);
-                }
-            }
-            mWebViewProvider.setEntries(options.toArray(new String[options.size()]));
-            mWebViewProvider.setEntryValues(values.toArray(new String[values.size()]));
-
-            String value = mWebViewUpdateService.getCurrentWebViewPackageName();
-            if (value == null) {
-                value = "";
-            }
-
-            for (int i = 0; i < values.size(); i++) {
-                if (value.contentEquals(values.get(i))) {
-                    mWebViewProvider.setValueIndex(i);
-                    return;
-                }
-            }
-        } catch (RemoteException e) {
-        }
-    }
-
     private void updateWebViewMultiprocessOptions() {
         try {
             updateSwitchPreference(mWebViewMultiprocess,
@@ -918,17 +886,6 @@ public class DevelopmentSettings extends RestrictedSettingsFragment
                 mBtHciSnoopLog.isChecked() ? 1 : 0);
     }
 
-    private boolean writeWebViewProviderOptions(Object newValue) {
-        try {
-            String updatedProvider = mWebViewUpdateService.changeProviderAndSetting(
-                    newValue == null ? "" : newValue.toString());
-            updateWebViewProviderOptions();
-            return newValue != null && newValue.equals(updatedProvider);
-        } catch (RemoteException e) {
-        }
-        return false;
-    }
-
     private void writeDebuggerOptions() {
         try {
             ActivityManager.getService().setDebugApp(
@@ -2327,6 +2284,8 @@ public class DevelopmentSettings extends RestrictedSettingsFragment
                 writeMockLocation();
                 updateMockLocation();
             }
+        } else if (requestCode == RESULT_WEBVIEW_APP) {
+            mWebViewAppPrefController.onActivityResult(resultCode, data);
         } else if (requestCode == REQUEST_CODE_ENABLE_OEM_UNLOCK) {
             if (resultCode == Activity.RESULT_OK) {
                 if (mEnableOemUnlock.isChecked()) {
@@ -2349,6 +2308,10 @@ public class DevelopmentSettings extends RestrictedSettingsFragment
         if (mBugReportInPowerController.handlePreferenceTreeClick(preference)) {
             return true;
         }
+        if (mWebViewAppPrefController.handlePreferenceTreeClick(preference)) {
+            startActivityForResult(
+                    mWebViewAppPrefController.getActivityIntent(), RESULT_WEBVIEW_APP);
+        }
 
         if (preference == mEnableAdb) {
             if (mEnableAdb.isChecked()) {
@@ -2502,21 +2465,6 @@ public class DevelopmentSettings extends RestrictedSettingsFragment
             updateHdcpValues();
             pokeSystemProperties();
             return true;
-        } else if (preference == mWebViewProvider) {
-            if (newValue == null) {
-                Log.e(TAG, "Tried to set a null WebView provider");
-                return false;
-            }
-            if (writeWebViewProviderOptions(newValue)) {
-                return true;
-            } else {
-                // The user chose a package that became invalid since the list was last updated,
-                // show a Toast to explain the situation.
-                Toast toast = Toast.makeText(getActivity(),
-                        R.string.select_webview_provider_toast_text, Toast.LENGTH_SHORT);
-                toast.show();
-            }
-            return false;
         } else if ((preference == mBluetoothSelectA2dpCodec) ||
                    (preference == mBluetoothSelectA2dpSampleRate) ||
                    (preference == mBluetoothSelectA2dpBitsPerSample) ||

src/com/android/settings/SettingsInitialize.java

@@ -44,6 +44,8 @@ public class SettingsInitialize extends BroadcastReceiver {
     private static final String TAG = "Settings";
     private static final String PRIMARY_PROFILE_SETTING =
             "com.android.settings.PRIMARY_PROFILE_CONTROLLED";
+    private static final String SETTINGS_PACKAGE = "com.android.settings";
+    private static final String WEBVIEW_IMPLEMENTATION_ACTIVITY = ".WebViewImplementation";
 
     @Override
     public void onReceive(Context context, Intent broadcast) {
@@ -100,7 +102,7 @@ public class SettingsInitialize extends BroadcastReceiver {
             return;
         }
         ComponentName settingsComponentName =
-            new ComponentName(context, WebViewImplementation.class);
+            new ComponentName(SETTINGS_PACKAGE, SETTINGS_PACKAGE + WEBVIEW_IMPLEMENTATION_ACTIVITY);
         pm.setComponentEnabledSetting(settingsComponentName,
                 userInfo.isAdmin() ?
                         PackageManager.COMPONENT_ENABLED_STATE_ENABLED :

src/com/android/settings/WebViewImplementation.java

@@ -1,114 +0,0 @@
-/*
- * Copyright (C) 2016 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;
-
-import android.annotation.Nullable;
-import android.app.AlertDialog;
-import android.content.DialogInterface;
-import android.content.DialogInterface.OnCancelListener;
-import android.content.DialogInterface.OnClickListener;
-import android.content.DialogInterface.OnDismissListener;
-import android.os.Bundle;
-import android.os.RemoteException;
-import android.os.ServiceManager;
-import android.os.UserManager;
-import android.util.Log;
-import android.webkit.IWebViewUpdateService;
-import android.webkit.WebViewProviderInfo;
-import com.android.internal.logging.nano.MetricsProto.MetricsEvent;
-import com.android.settings.core.InstrumentedActivity;
-
-import java.util.ArrayList;
-
-public class WebViewImplementation extends InstrumentedActivity implements
-        OnCancelListener, OnDismissListener {
-
-    private static final String TAG = "WebViewImplementation";
-
-    private IWebViewUpdateService mWebViewUpdateService;
-
-    @Override
-    protected void onCreate(@Nullable Bundle savedInstanceState) {
-        super.onCreate(savedInstanceState);
-        if (!UserManager.get(this).isAdminUser()) {
-            finish();
-            return;
-        }
-        mWebViewUpdateService  =
-                IWebViewUpdateService.Stub.asInterface(ServiceManager.getService("webviewupdate"));
-        try {
-            WebViewProviderInfo[] providers = mWebViewUpdateService.getValidWebViewPackages();
-            if (providers == null) {
-                Log.e(TAG, "No WebView providers available");
-                finish();
-                return;
-            }
-
-            String currentValue = mWebViewUpdateService.getCurrentWebViewPackageName();
-            if (currentValue == null) {
-                currentValue = "";
-            }
-
-            int currentIndex = -1;
-            ArrayList<String> options = new ArrayList<>();
-            final ArrayList<String> values = new ArrayList<>();
-            for (WebViewProviderInfo provider : providers) {
-                if (Utils.isPackageEnabled(this, provider.packageName)) {
-                    options.add(provider.description);
-                    values.add(provider.packageName);
-                    if (currentValue.contentEquals(provider.packageName)) {
-                        currentIndex = values.size() - 1;
-                    }
-                }
-            }
-
-            new AlertDialog.Builder(this)
-                    .setTitle(R.string.select_webview_provider_dialog_title)
-                    .setSingleChoiceItems(options.toArray(new String[0]), currentIndex,
-                            new OnClickListener() {
-                        @Override
-                        public void onClick(DialogInterface dialog, int which) {
-                            try {
-                                mWebViewUpdateService.changeProviderAndSetting(values.get(which));
-                            } catch (RemoteException e) {
-                                Log.w(TAG, "Problem reaching webviewupdate service", e);
-                            }
-                            finish();
-                        }
-                    }).setNegativeButton(android.R.string.cancel, null)
-                    .setOnCancelListener(this)
-                    .setOnDismissListener(this)
-                    .show();
-        } catch (RemoteException e) {
-            Log.w(TAG, "Problem reaching webviewupdate service", e);
-            finish();
-        }
-    }
-
-    @Override
-    public int getMetricsCategory() {
-        return MetricsEvent.WEBVIEW_IMPLEMENTATION;
-    }
-
-    @Override
-    public void onCancel(DialogInterface dialog) {
-        finish();
-    }
-
-    @Override
-    public void onDismiss(DialogInterface dialog) {
-        finish();
-    }
-}

src/com/android/settings/webview/UserPackageWrapper.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2017 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.webview;
+
+import android.content.Context;
+import android.content.pm.PackageInfo;
+import android.content.pm.UserInfo;
+import android.webkit.UserPackage;
+
+import java.util.List;
+
+/**
+ * Wrapper class around android.webkit.UserPackage - to be able to use UserPackage in Robolectric
+ * tests (such tests currently don't support mocking hidden classes).
+ */
+interface UserPackageWrapper {
+    UserInfo getUserInfo();
+    PackageInfo getPackageInfo();
+    boolean isEnabledPackage();
+    boolean isInstalledPackage();
+}

src/com/android/settings/webview/UserPackageWrapperImpl.java

@@ -0,0 +1,50 @@
+/*
+ * Copyright (C) 2017 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.webview;
+
+import android.content.Context;
+import android.content.pm.PackageInfo;
+import android.content.pm.UserInfo;
+import android.webkit.UserPackage;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Default implementation of UserPackageWrapper.
+ */
+class UserPackageWrapperImpl implements UserPackageWrapper {
+    private final UserPackage mUserPackage;
+
+    UserPackageWrapperImpl(UserPackage userPackage) {
+        mUserPackage = userPackage;
+    }
+
+    public UserInfo getUserInfo() {
+        return mUserPackage.getUserInfo();
+    }
+
+    public PackageInfo getPackageInfo() {
+        return mUserPackage.getPackageInfo();
+    }
+
+    public boolean isEnabledPackage() {
+        return mUserPackage.isEnabledPackage();
+    }
+
+    public boolean isInstalledPackage() {
+        return mUserPackage.isInstalledPackage();
+    }
+}

src/com/android/settings/webview/WebViewAppListAdapter.java

@@ -0,0 +1,126 @@
+/*
+ * Copyright (C) 2017 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.webview;
+
+import android.content.Context;
+import android.content.pm.ApplicationInfo;
+import android.content.pm.PackageManager;
+import android.os.RemoteException;
+import android.support.annotation.VisibleForTesting;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.ArrayAdapter;
+
+import com.android.settings.applications.AppViewHolder;
+import com.android.settings.R;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Custom list adapter for Settings to choose WebView package.
+ * Note: parts of this class are copied from AppPicker.java.
+ */
+class WebViewAppListAdapter extends ArrayAdapter<WebViewApplicationInfo> {
+    private final LayoutInflater mInflater;
+
+    public WebViewAppListAdapter(Context context,
+            WebViewUpdateServiceWrapper webviewUpdateServiceWrapper) {
+        super(context, 0);
+        mInflater = LayoutInflater.from(context);
+
+        final List<WebViewApplicationInfo> packageInfoList =
+                new ArrayList<WebViewApplicationInfo>();
+        List<ApplicationInfo> pkgs =
+                webviewUpdateServiceWrapper.getValidWebViewApplicationInfos(getContext());
+        for (ApplicationInfo ai : pkgs) {
+            WebViewApplicationInfo info = new WebViewApplicationInfo(ai,
+                    ai.loadLabel(context.getPackageManager()).toString(),
+                    getDisabledReason(webviewUpdateServiceWrapper, context, ai.packageName));
+            packageInfoList.add(info);
+        }
+        addAll(packageInfoList);
+    }
+
+    @Override
+    public View getView(int position, View convertView, ViewGroup parent) {
+        // A ViewHolder keeps references to children views to avoid unnecessary calls
+        // to findViewById() on each row.
+        AppViewHolder holder = AppViewHolder.createOrRecycle(mInflater, convertView);
+        convertView = holder.rootView;
+        WebViewApplicationInfo info = getItem(position);
+        holder.appName.setText(info.label);
+        if (info.info != null) {
+            holder.appIcon.setImageDrawable(info.info.loadIcon(getContext().getPackageManager()));
+            // Allow disable-description to wrap - to be able to show several lines of text in case
+            // a package is disabled/uninstalled for several users.
+            holder.summary.setSingleLine(false);
+            if (!isEnabled(position)) {
+                holder.summary.setText(info.disabledReason);
+            } else {
+                holder.summary.setText("");
+            }
+        } else {
+            holder.appIcon.setImageDrawable(null);
+            holder.summary.setText("");
+        }
+        holder.disabled.setVisibility(View.GONE);
+        // Only allow a package to be chosen if it is enabled and installed for all users.
+        convertView.setEnabled(isEnabled(position));
+        return convertView;
+    }
+
+    @Override
+    public boolean isEnabled (int position) {
+        WebViewApplicationInfo info = getItem(position);
+        return info.disabledReason == null;
+    }
+
+    @Override
+    public boolean areAllItemsEnabled() {
+        int numItems = getCount();
+        for (int n = 0; n < numItems; n++) {
+            if (!isEnabled(n)) return false;
+        }
+        return true;
+    }
+
+    /**
+     * Returns the reason why a package cannot be used as WebView implementation.
+     * This is either because of it being disabled, uninstalled, or hidden for any user.
+     */
+    @VisibleForTesting
+    static String getDisabledReason(WebViewUpdateServiceWrapper webviewUpdateServiceWrapper,
+            Context context, String packageName) {
+        StringBuilder disabledReason = new StringBuilder();
+        List<UserPackageWrapper> userPackages =
+                webviewUpdateServiceWrapper.getPackageInfosAllUsers(context, packageName);
+        for (UserPackageWrapper userPackage : userPackages) {
+            if (!userPackage.isInstalledPackage()) {
+                // Package uninstalled/hidden
+                disabledReason.append(context.getString(
+                        R.string.webview_uninstalled_for_user, userPackage.getUserInfo().name));
+            } else if (!userPackage.isEnabledPackage()) {
+                // Package disabled
+                disabledReason.append(context.getString(
+                    R.string.webview_disabled_for_user, userPackage.getUserInfo().name));
+            }
+        }
+        if (disabledReason.length() == 0) return null;
+        return disabledReason.toString();
+    }
+}
+

src/com/android/settings/webview/WebViewAppPicker.java

@@ -0,0 +1,95 @@
+/*
+ * Copyright (C) 2017 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.webview;
+
+import android.app.ListActivity;
+import android.content.pm.PackageInfo;
+import android.content.Context;
+import android.content.Intent;
+import android.os.Bundle;
+import android.os.RemoteException;
+import android.support.annotation.VisibleForTesting;
+import android.util.Log;
+import android.view.View;
+import android.webkit.WebViewFactory;
+import android.widget.ListView;
+
+import com.android.internal.logging.nano.MetricsProto.MetricsEvent;
+import com.android.settings.core.instrumentation.Instrumentable;
+import com.android.settings.core.instrumentation.VisibilityLoggerMixin;
+
+public class WebViewAppPicker extends ListActivity implements Instrumentable {
+    private static final String TAG = WebViewAppPicker.class.getSimpleName();
+    private WebViewAppListAdapter mAdapter;
+    private WebViewUpdateServiceWrapper mWebViewUpdateServiceWrapper;
+
+    private final VisibilityLoggerMixin mVisibilityLoggerMixin =
+            new VisibilityLoggerMixin(getMetricsCategory());
+
+    @Override
+    protected void onCreate(Bundle icicle) {
+        super.onCreate(icicle);
+
+        if (mWebViewUpdateServiceWrapper == null) {
+            setWebViewUpdateServiceWrapper(createDefaultWebViewUpdateServiceWrapper());
+        }
+        mAdapter = new WebViewAppListAdapter(this, mWebViewUpdateServiceWrapper);
+        setListAdapter(mAdapter);
+
+        mVisibilityLoggerMixin.onAttach(this);
+    }
+
+    @Override
+    protected void onListItemClick(ListView l, View v, int position, long id) {
+        WebViewApplicationInfo app = mAdapter.getItem(position);
+
+        if (mWebViewUpdateServiceWrapper.setWebViewProvider(app.info.packageName)) {
+            Intent intent = new Intent();
+            intent.setAction(app.info.packageName);
+            setResult(RESULT_OK, intent);
+        } else {
+            mWebViewUpdateServiceWrapper.showInvalidChoiceToast(this);
+        }
+        finish();
+    }
+
+    private WebViewUpdateServiceWrapper createDefaultWebViewUpdateServiceWrapper() {
+        return new WebViewUpdateServiceWrapper();
+    }
+
+    @VisibleForTesting
+    void setWebViewUpdateServiceWrapper(WebViewUpdateServiceWrapper wvusWrapper) {
+        mWebViewUpdateServiceWrapper = wvusWrapper;
+    }
+
+    @Override
+    public void onResume() {
+        super.onResume();
+        mVisibilityLoggerMixin.onResume();
+    }
+
+    @Override
+    public void onPause() {
+        super.onPause();
+        mVisibilityLoggerMixin.onPause();
+    }
+
+    @Override
+    public int getMetricsCategory() {
+        return MetricsEvent.WEBVIEW_IMPLEMENTATION;
+    }
+}

src/com/android/settings/webview/WebViewAppPreferenceController.java

@@ -0,0 +1,103 @@
+/*
+ * Copyright (C) 2017 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.webview;
+
+import android.app.Activity;
+import android.content.pm.PackageInfo;
+import android.content.Context;
+import android.content.Intent;
+import android.support.annotation.VisibleForTesting;
+import android.support.v7.preference.Preference;
+import android.support.v7.preference.PreferenceScreen;
+
+import com.android.settings.DevelopmentSettings;
+import com.android.settings.core.PreferenceController;
+
+public class WebViewAppPreferenceController extends PreferenceController {
+
+    private static final String WEBVIEW_APP_KEY = "select_webview_provider";
+
+    private Context mContext;
+    private Preference mPreference;
+    private final WebViewUpdateServiceWrapper mWebViewUpdateServiceWrapper;
+
+    public WebViewAppPreferenceController(Context context) {
+        this(context, new WebViewUpdateServiceWrapper());
+    }
+
+    public WebViewAppPreferenceController(Context context,
+            WebViewUpdateServiceWrapper webviewUpdateServiceWrapper) {
+        super(context);
+        mContext = context;
+        mWebViewUpdateServiceWrapper = webviewUpdateServiceWrapper;
+    }
+
+    @Override
+    public boolean handlePreferenceTreeClick(Preference preference) {
+        if (getPreferenceKey().equals(preference.getKey())) {
+            return true;
+        }
+        return false;
+    }
+
+    public Intent getActivityIntent() {
+        return new Intent(mContext, WebViewAppPicker.class);
+    }
+
+    @Override
+    public void updateState(Preference preference) {
+        mPreference.setSummary(getCurrentWebViewPackageLabel(mContext));
+    }
+
+    @Override
+    public void displayPreference(PreferenceScreen screen) {
+        super.displayPreference(screen);
+        if (isAvailable()) {
+            mPreference = screen.findPreference(WEBVIEW_APP_KEY);
+        }
+    }
+
+    /**
+     * Handle the return-value from the WebViewAppPicker Activity.
+     */
+    public void onActivityResult(int resultCode, Intent data) {
+        if (resultCode == Activity.RESULT_OK) {
+            updateState(null);
+        }
+    }
+
+    private String getCurrentWebViewPackageLabel(Context context) {
+        PackageInfo webViewPackage = mWebViewUpdateServiceWrapper.getCurrentWebViewPackage();
+        if (webViewPackage == null) return "";
+        return webViewPackage.applicationInfo.loadLabel(context.getPackageManager()).toString();
+    }
+
+
+    @Override
+    public String getPreferenceKey() {
+        return WEBVIEW_APP_KEY;
+    }
+
+    @Override
+    public boolean isAvailable() {
+        return true;
+    }
+
+    public void enablePreference(boolean enabled) {
+        if (isAvailable()) {
+            mPreference.setEnabled(enabled);
+        }
+    }
+}

src/com/android/settings/webview/WebViewApplicationInfo.java

@@ -0,0 +1,29 @@
+/*
+ * Copyright (C) 2017 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.webview;
+
+import android.content.pm.ApplicationInfo;
+
+final class WebViewApplicationInfo {
+    final ApplicationInfo info;
+    final String label;
+    final String disabledReason;
+
+    public WebViewApplicationInfo(ApplicationInfo info, String label, String disabledReason) {
+        this.info = info;
+        this.label = label;
+        this.disabledReason = disabledReason;
+    }
+}

src/com/android/settings/webview/WebViewUpdateServiceWrapper.java

@@ -0,0 +1,113 @@
+/*
+ * Copyright (C) 2017 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.webview;
+
+import android.content.Context;
+import android.content.pm.ApplicationInfo;
+import android.content.pm.PackageInfo;
+import android.content.pm.PackageManager;
+import android.os.RemoteException;
+import android.util.Log;
+import android.webkit.UserPackage;
+import android.webkit.WebViewFactory;
+import android.webkit.WebViewProviderInfo;
+import android.widget.Toast;
+
+import com.android.settings.R;
+
+import java.util.ArrayList;
+import java.util.List;
+
+class WebViewUpdateServiceWrapper {
+    private static final String TAG = "WVUSWrapper";
+
+    public WebViewUpdateServiceWrapper() {}
+
+    /**
+     * Fetch the package currently used as WebView implementation.
+     */
+    public PackageInfo getCurrentWebViewPackage() {
+        try {
+            return WebViewFactory.getUpdateService().getCurrentWebViewPackage();
+        } catch (RemoteException e) {
+            Log.e(TAG, e.toString());
+        }
+        return null;
+    }
+
+    /**
+     * Fetches ApplicationInfo objects for all currently valid WebView packages.
+     * A WebView package is considered valid if it can be used as a WebView implementation. The
+     * validity of a package is not dependent on whether the package is installed/enabled.
+     */
+    public List<ApplicationInfo> getValidWebViewApplicationInfos(Context context) {
+        WebViewProviderInfo[] providers = null;
+        try {
+            providers = WebViewFactory.getUpdateService().getValidWebViewPackages();
+        } catch (RemoteException e) {
+        }
+        List<ApplicationInfo> pkgs = new ArrayList<>();
+        for (WebViewProviderInfo provider : providers) {
+            try {
+                pkgs.add(context.getPackageManager().getApplicationInfo(
+                        provider.packageName, PACKAGE_FLAGS));
+            } catch (PackageManager.NameNotFoundException e) {
+            }
+        }
+        return pkgs;
+    }
+
+    /**
+     * Change WebView provider to {@param packageName}.
+     * @return whether the change succeeded.
+     */
+    public boolean setWebViewProvider(String packageName) {
+        try {
+            return packageName.equals(
+                    WebViewFactory.getUpdateService().changeProviderAndSetting(packageName));
+        } catch (RemoteException e) {
+            Log.e(TAG, "RemoteException when trying to change provider to " + packageName, e);
+        }
+        return false;
+    }
+
+    /**
+     * Fetch PackageInfos for the package named {@param packageName} for all users on the device.
+     */
+    public List<UserPackageWrapper> getPackageInfosAllUsers(Context context, String packageName) {
+        List<UserPackageWrapper> userPackageWrappers = new ArrayList<>();
+        List<UserPackage> userPackages =
+                UserPackage.getPackageInfosAllUsers(context, packageName, PACKAGE_FLAGS);
+        for (UserPackage userPackage : userPackages) {
+            userPackageWrappers.add(new UserPackageWrapperImpl(userPackage));
+        }
+        return userPackageWrappers;
+    }
+
+    /**
+     * Show a toast to explain the chosen package can no longer be chosen.
+     */
+    public void showInvalidChoiceToast(Context context) {
+        // The user chose a package that became invalid since the list was last updated,
+        // show a Toast to explain the situation.
+        Toast toast = Toast.makeText(context,
+                R.string.select_webview_provider_toast_text, Toast.LENGTH_SHORT);
+        toast.show();
+    }
+
+    static final int PACKAGE_FLAGS = PackageManager.MATCH_ANY_USER;
+}