Notification listeners can be enabled in Settings>Security.

Also known as android.settings.ACTION_NOTIFICATION_LISTENER_SETTINGS.

Bug: 8454150
Change-Id: I0c2433bf58ba4c78cd461326bd014535c7f67578
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 143a394..e9218e1 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -1572,6 +1572,21 @@
                 android:resource="@id/user_settings" />
         </activity>
 
+        <activity android:name="Settings$NotificationAccessSettingsActivity"
+                  android:label="@string/manage_notification_access"
+                  android:taskAffinity=""
+                  android:excludeFromRecents="true">
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+                <action android:name="android.settings.ACTION_NOTIFICATION_LISTENER_SETTINGS" />
+                <category android:name="android.intent.category.DEFAULT" />
+            </intent-filter>
+            <meta-data android:name="com.android.settings.FRAGMENT_CLASS"
+                       android:value="com.android.settings.NotificationAccessSettings" />
+            <meta-data android:name="com.android.settings.TOP_LEVEL_HEADER_ID"
+                       android:resource="@id/security_settings" />
+        </activity>
+
         <receiver android:name=".widget.SettingsAppWidgetProvider"
                 android:label="@string/gadget_title"
                 android:exported="true"
diff --git a/res/layout/notification_access_settings.xml b/res/layout/notification_access_settings.xml
new file mode 100644
index 0000000..db1f708
--- /dev/null
+++ b/res/layout/notification_access_settings.xml
@@ -0,0 +1,37 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- 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.
+-->
+
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical">
+    <FrameLayout
+            android:layout_width="match_parent"
+            android:layout_height="0px"
+            android:layout_weight="1">
+        <ListView android:id="@android:id/list"
+                android:layout_width="match_parent" 
+                android:layout_height="match_parent"
+                android:drawSelectorOnTop="false"
+                android:fastScrollEnabled="true" />
+        <TextView android:id="@android:id/empty"
+                android:layout_width="match_parent"
+                android:layout_height="match_parent"
+                android:gravity="center"
+                android:text="@string/no_notification_listeners"
+                android:textAppearance="?android:attr/textAppearanceMedium" />
+    </FrameLayout>
+</LinearLayout>
diff --git a/res/layout/notification_listener_item.xml b/res/layout/notification_listener_item.xml
new file mode 100644
index 0000000..67aaa61
--- /dev/null
+++ b/res/layout/notification_listener_item.xml
@@ -0,0 +1,77 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+/*
+** Copyright 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.
+*/
+-->
+
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:minHeight="?android:attr/listPreferredItemHeight"
+    android:orientation="horizontal"
+    android:paddingEnd="6dip"
+    android:gravity="center_vertical"
+    >
+
+    <ImageView
+        android:id="@+id/icon"
+        android:layout_width="@android:dimen/app_icon_size"
+        android:layout_height="@android:dimen/app_icon_size"
+        android:layout_gravity="center_vertical"
+        android:scaleType="centerInside"
+        android:contentDescription="@null"
+        />
+
+    <LinearLayout
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginStart="8dp"
+        android:layout_marginTop="8dip"
+        android:layout_marginBottom="8dip"
+        android:orientation="vertical"
+        android:gravity="left|center_vertical"
+        android:layout_weight="1">
+
+        <TextView android:id="@+id/name"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:singleLine="true"
+            android:textAppearance="?android:attr/textAppearanceMedium"
+            android:ellipsize="marquee"
+            android:fadingEdge="horizontal" />
+
+        <TextView android:id="@+id/description"
+            android:visibility="gone"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_marginTop="4dip"
+            android:textAppearance="?android:attr/textAppearanceSmall"
+            android:textColor="?android:attr/textColorSecondary"
+            android:maxLines="4" />
+
+    </LinearLayout>
+
+    <CheckBox xmlns:android="http://schemas.android.com/apk/res/android"
+        android:id="@+id/checkbox"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="center_vertical"
+        android:layout_marginEnd="16dip"
+        android:layout_marginStart="16dip"
+        android:focusable="false"
+        android:clickable="false" />
+
+</LinearLayout>
diff --git a/res/values/strings.xml b/res/values/strings.xml
index 573f4a0..e56c049 100644
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -983,6 +983,37 @@
     <!-- Summary of preference to manage device policies -->
     <string name="manage_device_admin_summary">View or deactivate device administrators</string>
 
+    <!-- Notification access settings (part of Security) -->
+
+    <!-- Title of preference to manage notification listeners -->
+    <string name="manage_notification_access">Notification access</string>
+
+    <!-- Summary of preference to manage notification listeners, when none are enabled -->
+    <string name="manage_notification_access_summary_zero">Apps cannot read notifications</string>
+
+    <!-- Summary of preference to manage notification listeners, when one or more are enabled
+         and are therefore able to read the user's notifications -->
+    <plurals name="manage_notification_access_summary_nonzero">
+        <item quantity="one">%d app can read notifications</item>
+        <item quantity="other">%d apps can read notifications</item>
+    </plurals>
+
+    <!-- String to show in the list of notification listeners, when none is installed -->
+    <string name="no_notification_listeners">No notification listeners are installed.</string>
+
+    <!-- Title for a warning message about security implications of enabling a notification
+          listener, displayed as a dialog message. [CHAR LIMIT=NONE] -->
+    <string name="notification_listener_security_warning_title">Enable
+         <xliff:g id="service" example="NotificationReader">%1$s</xliff:g>?</string>
+    <!-- Summary for a warning message about security implications of enabling a notification
+          listener, displayed as a dialog message. [CHAR LIMIT=NONE] -->
+    <string name="notification_listener_security_warning_summary">
+        <xliff:g id="notification_listener_name">%1$s</xliff:g> will be able to 
+        read all notifications posted by the system or any installed app, which may include personal
+        information such as contact names and the text of messages sent to you. It will also be able
+        to dismiss these notifications or touch action buttons within them.
+    </string>
+
     <!-- Bluetooth settings -->
     <!-- Bluetooth settings check box title on Main Settings screen -->
     <string name="bluetooth_quick_toggle_title">Bluetooth</string>
diff --git a/res/xml/security_settings_misc.xml b/res/xml/security_settings_misc.xml
index 10fc98f..1ead7a9 100644
--- a/res/xml/security_settings_misc.xml
+++ b/res/xml/security_settings_misc.xml
@@ -58,6 +58,13 @@
                 android:summaryOff="@string/verify_applications_summary"
                 android:summaryOn="@string/verify_applications_summary"
                 android:persistent="false" />
+
+        <Preference
+                android:key="manage_notification_access"
+                android:title="@string/manage_notification_access"
+                android:persistent="false"
+                android:fragment="com.android.settings.NotificationAccessSettings"/>
+
     </PreferenceCategory>
 
     <PreferenceCategory android:key="credentials_management"
diff --git a/src/com/android/settings/NotificationAccessSettings.java b/src/com/android/settings/NotificationAccessSettings.java
new file mode 100644
index 0000000..ed81d59
--- /dev/null
+++ b/src/com/android/settings/NotificationAccessSettings.java
@@ -0,0 +1,312 @@
+/*
+ * Copyright (C) 2010 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.app.ActivityManager;
+import android.app.AlertDialog;
+import android.app.Dialog;
+import android.app.DialogFragment;
+import android.content.BroadcastReceiver;
+import android.content.ContentResolver;
+import android.content.DialogInterface;
+import android.content.IntentFilter;
+import android.content.pm.PackageItemInfo;
+import android.content.pm.ServiceInfo;
+import android.database.ContentObserver;
+import android.net.Uri;
+import android.os.Handler;
+import android.service.notification.NotificationListenerService;
+import android.util.Slog;
+import android.widget.ArrayAdapter;
+
+import android.app.ListFragment;
+import android.content.ComponentName;
+import android.content.Context;
+import android.content.Intent;
+import android.content.pm.PackageManager;
+import android.content.pm.ResolveInfo;
+import android.os.Bundle;
+import android.provider.Settings;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.CheckBox;
+import android.widget.ImageView;
+import android.widget.ListView;
+import android.widget.TextView;
+
+import java.util.HashSet;
+import java.util.List;
+
+public class NotificationAccessSettings extends ListFragment {
+    static final String TAG = NotificationAccessSettings.class.getSimpleName();
+    private static final boolean SHOW_PACKAGE_NAME = false;
+
+    private PackageManager mPM;
+    private ContentResolver mCR;
+
+    private final HashSet<ComponentName> mEnabledListeners = new HashSet<ComponentName>();
+    private ListenerListAdapter mList;
+
+    private final Uri ENABLED_NOTIFICATION_LISTENERS_URI
+            = Settings.Secure.getUriFor(Settings.Secure.ENABLED_NOTIFICATION_LISTENERS);
+
+    private final ContentObserver mSettingsObserver = new ContentObserver(new Handler()) {
+        @Override
+        public void onChange(boolean selfChange, Uri uri) {
+            updateList();
+        }
+    };
+
+    private final BroadcastReceiver mPackageReceiver = new BroadcastReceiver() {
+        @Override
+        public void onReceive(Context context, Intent intent) {
+            updateList();
+        }
+    };
+
+    public class ListenerWarningDialogFragment extends DialogFragment {
+        static final String KEY_COMPONENT = "c";
+        static final String KEY_LABEL = "l";
+
+        public ListenerWarningDialogFragment setListenerInfo(ComponentName cn, String label) {
+            Bundle args = new Bundle();
+            args.putString(KEY_COMPONENT, cn.flattenToString());
+            args.putString(KEY_LABEL, label);
+            setArguments(args);
+
+            return this;
+        }
+        @Override
+        public Dialog onCreateDialog(Bundle savedInstanceState) {
+            super.onCreate(savedInstanceState);
+            final Bundle args = getArguments();
+            final String label = args.getString(KEY_LABEL);
+            final ComponentName cn = ComponentName.unflattenFromString(args.getString(KEY_COMPONENT));
+
+            final String title = getResources().getString(
+                    R.string.notification_listener_security_warning_title, label);
+            final String summary = getResources().getString(
+                    R.string.notification_listener_security_warning_summary, label);
+            return new AlertDialog.Builder(getActivity())
+                    .setMessage(summary)
+                    .setTitle(title)
+                    .setIconAttribute(android.R.attr.alertDialogIcon)
+                    .setCancelable(true)
+                    .setPositiveButton(android.R.string.ok,
+                            new DialogInterface.OnClickListener() {
+                                public void onClick(DialogInterface dialog, int id) {
+                                    mEnabledListeners.add(cn);
+                                    saveEnabledListeners();
+                                }
+                            })
+                    .setNegativeButton(android.R.string.cancel,
+                            new DialogInterface.OnClickListener() {
+                                public void onClick(DialogInterface dialog, int id) {
+                                    // pass
+                                }
+                            })
+                    .create();
+        }
+    }
+
+    @Override
+    public void onCreate(Bundle icicle) {
+        super.onCreate(icicle);
+
+        mPM = getActivity().getPackageManager();
+        mCR = getActivity().getContentResolver();
+        mList = new ListenerListAdapter(getActivity());
+    }
+
+    @Override
+    public View onCreateView(LayoutInflater inflater, ViewGroup container,
+            Bundle savedInstanceState) {
+        return inflater.inflate(R.layout.device_admin_settings, container, false);
+    }
+
+    @Override
+    public void onResume() {
+        super.onResume();
+        updateList();
+
+        // listen for package changes
+        IntentFilter filter = new IntentFilter();
+        filter.addAction(Intent.ACTION_PACKAGE_ADDED);
+        filter.addAction(Intent.ACTION_PACKAGE_CHANGED);
+        filter.addAction(Intent.ACTION_PACKAGE_REMOVED);
+        filter.addAction(Intent.ACTION_PACKAGE_REPLACED);
+        filter.addDataScheme("package");
+        getActivity().registerReceiver(mPackageReceiver, filter);
+
+        mCR.registerContentObserver(ENABLED_NOTIFICATION_LISTENERS_URI, false, mSettingsObserver);
+    }
+
+    @Override
+    public void onPause() {
+        super.onPause();
+
+        getActivity().unregisterReceiver(mPackageReceiver);
+        mCR.unregisterContentObserver(mSettingsObserver);
+    }
+
+    void loadEnabledListeners() {
+        mEnabledListeners.clear();
+        final String flat = Settings.Secure.getString(mCR,
+                Settings.Secure.ENABLED_NOTIFICATION_LISTENERS);
+        if (flat != null && !"".equals(flat)) {
+            final String[] names = flat.split(":");
+            for (int i = 0; i < names.length; i++) {
+                final ComponentName cn = ComponentName.unflattenFromString(names[i]);
+                if (cn != null) {
+                    mEnabledListeners.add(cn);
+                }
+            }
+        }
+    }
+
+    void saveEnabledListeners() {
+        StringBuilder sb = null;
+        for (ComponentName cn : mEnabledListeners) {
+            if (sb == null) {
+                sb = new StringBuilder();
+            } else {
+                sb.append(':');
+            }
+            sb.append(cn.flattenToString());
+        }
+        Settings.Secure.putString(mCR,
+                Settings.Secure.ENABLED_NOTIFICATION_LISTENERS,
+                sb != null ? sb.toString() : "");
+    }
+
+    void updateList() {
+        mList.clear();
+
+        loadEnabledListeners();
+
+        final int user = ActivityManager.getCurrentUser();
+
+        List<ResolveInfo> installedServices = mPM.queryIntentServicesAsUser(
+                new Intent(NotificationListenerService.SERVICE_INTERFACE),
+                PackageManager.GET_SERVICES | PackageManager.GET_META_DATA,
+                user);
+
+        for (int i = 0, count = installedServices.size(); i < count; i++) {
+            ResolveInfo resolveInfo = installedServices.get(i);
+            ServiceInfo info = resolveInfo.serviceInfo;
+
+            if (!android.Manifest.permission.BIND_NOTIFICATION_LISTENER_SERVICE.equals(
+                    info.permission)) {
+                Slog.w(TAG, "Skipping notification listener service "
+                        + info.packageName + "/" + info.name
+                        + ": it does not require the permission "
+                        + android.Manifest.permission.BIND_NOTIFICATION_LISTENER_SERVICE);
+                continue;
+            }
+
+            mList.add(info);
+        }
+
+        mList.sort(new PackageItemInfo.DisplayNameComparator(mPM));
+
+        getListView().setAdapter(mList);
+    }
+
+    boolean isListenerEnabled(ServiceInfo info) {
+        final ComponentName cn = new ComponentName(info.packageName, info.name);
+        return mEnabledListeners.contains(cn);
+    }
+
+    @Override
+    public void onListItemClick(ListView l, View v, int position, long id) {
+        ServiceInfo info = mList.getItem(position);
+        final ComponentName cn = new ComponentName(info.packageName, info.name);
+        if (mEnabledListeners.contains(cn)) {
+            // the simple version: disabling
+            mEnabledListeners.remove(cn);
+            saveEnabledListeners();
+        } else {
+            // show a scary dialog
+            new ListenerWarningDialogFragment()
+                .setListenerInfo(cn, info.loadLabel(mPM).toString())
+                .show(getFragmentManager(), "dialog");
+        }
+    }
+
+    static class ViewHolder {
+        ImageView icon;
+        TextView name;
+        CheckBox checkbox;
+        TextView description;
+    }
+
+    class ListenerListAdapter extends ArrayAdapter<ServiceInfo> {
+        final LayoutInflater mInflater;
+
+        ListenerListAdapter(Context context) {
+            super(context, 0, 0);
+            mInflater = (LayoutInflater)
+                    getActivity().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
+        }
+
+        public boolean hasStableIds() {
+            return true;
+        }
+
+        public long getItemId(int position) {
+            return position;
+        }
+
+        public View getView(int position, View convertView, ViewGroup parent) {
+            View v;
+            if (convertView == null) {
+                v = newView(parent);
+            } else {
+                v = convertView;
+            }
+            bindView(v, position);
+            return v;
+        }
+
+        public View newView(ViewGroup parent) {
+            View v = mInflater.inflate(R.layout.notification_listener_item, parent, false);
+            ViewHolder h = new ViewHolder();
+            h.icon = (ImageView) v.findViewById(R.id.icon);
+            h.name = (TextView) v.findViewById(R.id.name);
+            h.checkbox = (CheckBox) v.findViewById(R.id.checkbox);
+            h.description = (TextView) v.findViewById(R.id.description);
+            v.setTag(h);
+            return v;
+        }
+
+        public void bindView(View view, int position) {
+            ViewHolder vh = (ViewHolder) view.getTag();
+            ServiceInfo info = getItem(position);
+
+            vh.icon.setImageDrawable(info.loadIcon(mPM));
+            vh.name.setText(info.loadLabel(mPM));
+            if (SHOW_PACKAGE_NAME) {
+                vh.description.setText(info.packageName);
+                vh.description.setVisibility(View.VISIBLE);
+            } else {
+                vh.description.setVisibility(View.GONE);
+            }
+            vh.checkbox.setChecked(isListenerEnabled(info));
+        }
+    }
+}
diff --git a/src/com/android/settings/SecuritySettings.java b/src/com/android/settings/SecuritySettings.java
index 971a196..d75d630 100644
--- a/src/com/android/settings/SecuritySettings.java
+++ b/src/com/android/settings/SecuritySettings.java
@@ -79,6 +79,7 @@
     private static final String KEY_TOGGLE_VERIFY_APPLICATIONS = "toggle_verify_applications";
     private static final String KEY_POWER_INSTANTLY_LOCKS = "power_button_instantly_locks";
     private static final String KEY_CREDENTIALS_MANAGER = "credentials_management";
+    private static final String KEY_NOTIFICATION_ACCESS = "manage_notification_access";
     private static final String PACKAGE_MIME_TYPE = "application/vnd.android.package-archive";
 
     DevicePolicyManager mDPM;
@@ -100,6 +101,8 @@
     private CheckBoxPreference mToggleVerifyApps;
     private CheckBoxPreference mPowerButtonInstantlyLocks;
 
+    private Preference mNotificationAccess;
+
     private boolean mIsPrimary;
 
     @Override
@@ -283,9 +286,28 @@
             }
         }
 
+        final int n = getNumEnabledNotificationListeners();
+        mNotificationAccess = findPreference(KEY_NOTIFICATION_ACCESS);
+        if (n == 0) {
+            mNotificationAccess.setSummary(getResources().getString(
+                    R.string.manage_notification_access_summary_zero));
+        } else {
+            mNotificationAccess.setSummary(String.format(getResources().getQuantityString(
+                    R.plurals.manage_notification_access_summary_nonzero,
+                    n, n)));
+        }
+
         return root;
     }
 
+    private int getNumEnabledNotificationListeners() {
+        final String flat = Settings.Secure.getString(getContentResolver(),
+                Settings.Secure.ENABLED_NOTIFICATION_LISTENERS);
+        if (flat == null || "".equals(flat)) return 0;
+        final String[] components = flat.split(":");
+        return components.length;
+    }
+
     private boolean isNonMarketAppsAllowed() {
         return Settings.Global.getInt(getContentResolver(),
                                       Settings.Global.INSTALL_NON_MARKET_APPS, 0) > 0;
diff --git a/src/com/android/settings/Settings.java b/src/com/android/settings/Settings.java
index e29874b..ed3685d 100644
--- a/src/com/android/settings/Settings.java
+++ b/src/com/android/settings/Settings.java
@@ -840,4 +840,5 @@
     public static class DreamSettingsActivity extends Settings { /* empty */ }
     public static class NotificationStationActivity extends Settings { /* empty */ }
     public static class UserSettingsActivity extends Settings { /* empty */ }
+    public static class NotificationAccessSettingsActivity extends Settings { /* empty */ }
 }