example notification listener

demonstrate order-sensitive features of the listeners
also launch contentIntents and handle dismissal

Change-Id: I9e58c72a8d570f4b9a23e4642632b19fcd682dca
Depends-On: I7244c65944a9657df41fb313b3cb5a52e149709d

16 files changed, 774 insertions, 0 deletions

diff --git a/NotificationListenerSample/Android.mk b/NotificationListenerSample/Android.mk
new file mode 100644
index 0000000..5075a96
--- /dev/null
+++ b/NotificationListenerSample/Android.mk
@@ -0,0 +1,33 @@
+#
+# Copyright (C) 2014 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.
+#
+
+LOCAL_PATH:= $(call my-dir)
+
+include $(CLEAR_VARS)
+
+LOCAL_MODULE_TAGS := optional
+
+LOCAL_AAPT_FLAGS += -c mdpi,hdpi,xhdpi
+
+LOCAL_SRC_FILES := $(call all-java-files-under, src)
+
+LOCAL_STATIC_JAVA_LIBRARIES := android-support-v4
+
+LOCAL_PACKAGE_NAME := NotificationListenerSample
+LOCAL_CERTIFICATE := platform
+include $(BUILD_PACKAGE)
+
+include $(call all-makefiles-under,$(LOCAL_PATH))
diff --git a/NotificationListenerSample/AndroidManifest.xml b/NotificationListenerSample/AndroidManifest.xml
new file mode 100644
index 0000000..e36d422
--- /dev/null
+++ b/NotificationListenerSample/AndroidManifest.xml
@@ -0,0 +1,37 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2014 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.
+-->
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+      package="com.android.example.notificationlistener"
+      android:versionCode="1"
+      android:versionName="1.0">
+
+    <application android:icon="@drawable/icon" android:label="@string/app_name">
+        <activity android:name=".NotificationListenerActivity"
+                  android:label="@string/app_name">
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+                <category android:name="android.intent.category.LAUNCHER" />
+            </intent-filter>
+        </activity>
+        <service android:name="com.android.example.notificationlistener.Listener"
+                 android:label="@string/service_name"
+                 android:permission="android.permission.BIND_NOTIFICATION_LISTENER_SERVICE">
+            <intent-filter>
+                <action android:name="android.service.notification.NotificationListenerService" />
+            </intent-filter>
+        </service>
+    </application>
+</manifest>
diff --git a/NotificationListenerSample/res/drawable-hdpi/dialog_ic_dismiss.png b/NotificationListenerSample/res/drawable-hdpi/dialog_ic_dismiss.png
new file mode 100644
index 0000000..1aca4b7
--- /dev/null
+++ b/NotificationListenerSample/res/drawable-hdpi/dialog_ic_dismiss.png
diff --git a/NotificationListenerSample/res/drawable-hdpi/icon.png b/NotificationListenerSample/res/drawable-hdpi/icon.png
new file mode 100644
index 0000000..bc976fa
--- /dev/null
+++ b/NotificationListenerSample/res/drawable-hdpi/icon.png
diff --git a/NotificationListenerSample/res/drawable-mdpi/dialog_ic_dismiss.png b/NotificationListenerSample/res/drawable-mdpi/dialog_ic_dismiss.png
new file mode 100644
index 0000000..6a2fb5e
--- /dev/null
+++ b/NotificationListenerSample/res/drawable-mdpi/dialog_ic_dismiss.png
diff --git a/NotificationListenerSample/res/drawable-mdpi/icon.png b/NotificationListenerSample/res/drawable-mdpi/icon.png
new file mode 100644
index 0000000..e8f7538
--- /dev/null
+++ b/NotificationListenerSample/res/drawable-mdpi/icon.png
diff --git a/NotificationListenerSample/res/drawable-xhdpi/dialog_ic_dismiss.png b/NotificationListenerSample/res/drawable-xhdpi/dialog_ic_dismiss.png
new file mode 100644
index 0000000..e11f2e3
--- /dev/null
+++ b/NotificationListenerSample/res/drawable-xhdpi/dialog_ic_dismiss.png
diff --git a/NotificationListenerSample/res/drawable-xhdpi/icon.png b/NotificationListenerSample/res/drawable-xhdpi/icon.png
new file mode 100644
index 0000000..002515c
--- /dev/null
+++ b/NotificationListenerSample/res/drawable-xhdpi/icon.png
diff --git a/NotificationListenerSample/res/drawable-xxhdpi/dialog_ic_dismiss.png b/NotificationListenerSample/res/drawable-xxhdpi/dialog_ic_dismiss.png
new file mode 100644
index 0000000..8d185f4
--- /dev/null
+++ b/NotificationListenerSample/res/drawable-xxhdpi/dialog_ic_dismiss.png
diff --git a/NotificationListenerSample/res/drawable-xxhdpi/icon.png b/NotificationListenerSample/res/drawable-xxhdpi/icon.png
new file mode 100644
index 0000000..e78554f
--- /dev/null
+++ b/NotificationListenerSample/res/drawable-xxhdpi/icon.png
diff --git a/NotificationListenerSample/res/layout/item.xml b/NotificationListenerSample/res/layout/item.xml
new file mode 100644
index 0000000..2d9a5ed
--- /dev/null
+++ b/NotificationListenerSample/res/layout/item.xml
@@ -0,0 +1,32 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2014 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.
+-->
+<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
+              android:layout_height="match_parent"
+              android:layout_width="wrap_content"
+              android:padding="4dp">
+    <FrameLayout android:id="@+id/remote_view"
+                 android:layout_height="match_parent"
+                 android:layout_width="wrap_content"
+                 android:onClick="launch"
+            />
+    <ImageButton android:id="@+id/dismiss"
+                 android:layout_width="wrap_content"
+                 android:layout_height="wrap_content"
+                 android:layout_gravity="top|end"
+                 android:src="@drawable/dialog_ic_dismiss"
+                 android:onClick="dismiss"
+            />
+</FrameLayout>
\ No newline at end of file
diff --git a/NotificationListenerSample/res/layout/main.xml b/NotificationListenerSample/res/layout/main.xml
new file mode 100644
index 0000000..44c9da4
--- /dev/null
+++ b/NotificationListenerSample/res/layout/main.xml
@@ -0,0 +1,50 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2014 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"
+              android:padding="12dp"
+        >
+    <ListView
+            android:id="@android:id/list"
+            android:layout_width="match_parent"
+            android:layout_height="0dp"
+            android:padding="4dp"
+            android:layout_marginBottom="16dp"
+            android:text="@string/working_as_intended"
+            android:layout_weight="1"
+            android:choiceMode="singleChoice"
+            />
+
+    <TextView android:id="@android:id/empty"
+              android:layout_width="match_parent"
+              android:layout_height="0dp"
+              android:padding="4dp"
+              android:layout_marginBottom="16dp"
+              android:text="@string/working_as_intended"
+              android:layout_weight="1"
+            />
+    <Button
+            android:id="@+id/launch_settings"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:text="@string/launch_to_disable"
+            android:onClick="launchSettings"
+            android:layout_weight="0"
+            />
+</LinearLayout>
+
diff --git a/NotificationListenerSample/res/values/strings.xml b/NotificationListenerSample/res/values/strings.xml
new file mode 100644
index 0000000..5c74fda
--- /dev/null
+++ b/NotificationListenerSample/res/values/strings.xml
@@ -0,0 +1,31 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2014 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.
+-->
+<resources>
+    <string name="app_name">NotificationListener</string>
+    <string name="long_app_name">Notification Listener Sample</string>
+    <string name="service_name">Sample Notification Listener</string>
+    <string name="working_as_intended">Service is running.  Disable it in Security Settings.</string>
+    <string name="waiting_for_content">Service is running.  Waiting for notifications to arrive.</string>
+    <string name="nothing_to_see">Service is disabled.  You must enabled it to see notifications.</string>
+    <string name="launch_to_disable">Press to disable service</string>
+    <string name="launch_to_enable">Press to enable service</string>
+    <string name="explanation">This app demonstrates use of the Notification Listener Service API.
+        You must enable the listener service in Security Settings to see it work.
+    </string>
+    <string name="disabled">Service is not running.</string>
+    <string name="enable_it">Enable</string>
+    <string name="cancel">Cancel</string>
+</resources>
diff --git a/NotificationListenerSample/src/com/android/example/notificationlistener/Listener.java b/NotificationListenerSample/src/com/android/example/notificationlistener/Listener.java
new file mode 100644
index 0000000..1ddb0e7
--- /dev/null
+++ b/NotificationListenerSample/src/com/android/example/notificationlistener/Listener.java
@@ -0,0 +1,237 @@
+/*
+ * Copyright (C) 2014 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.example.notificationlistener;
+
+
+import android.app.Notification;
+import android.app.PendingIntent;
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.os.Handler;
+import android.os.Message;
+import android.service.notification.NotificationListenerService;
+import android.service.notification.StatusBarNotification;
+import android.support.v4.content.LocalBroadcastManager;
+import android.text.TextUtils;
+import android.util.Log;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+
+public class Listener extends NotificationListenerService {
+    private static final String TAG = "SampleListener";
+
+    // Message tags
+    private static final int MSG_NOTIFY = 1;
+    private static final int MSG_CANCEL = 2;
+    private static final int MSG_STARTUP = 3;
+    private static final int MSG_ORDER = 4;
+    private static final int MSG_DISMISS = 5;
+    private static final int MSG_LAUNCH = 6;
+    private static final int PAGE = 10;
+
+    static final String ACTION_DISMISS = "com.android.example.notificationlistener.DISMISS";
+    static final String ACTION_LAUNCH = "com.android.example.notificationlistener.LAUNCH";
+    static final String ACTION_REFRESH = "com.android.example.notificationlistener.REFRESH";
+    static final String EXTRA_KEY = "key";
+
+    private static ArrayList<StatusBarNotification> sNotifications;
+
+    public static List<StatusBarNotification> getNotifications() {
+        return sNotifications;
+    }
+
+    private OrderedNotificationsHelper mOrderHelper;
+
+    private class Delta {
+        final StatusBarNotification mSbn;
+        final String[] mKeys;
+
+        public Delta(StatusBarNotification sbn, String[] update) {
+            mSbn = sbn;
+            mKeys = update;
+        }
+    }
+
+    private final BroadcastReceiver mBroadcastReceiver = new BroadcastReceiver() {
+        @Override
+        public void onReceive(Context context, Intent intent) {
+            String key = intent.getStringExtra(EXTRA_KEY);
+            int what = MSG_DISMISS;
+            if (ACTION_LAUNCH.equals(intent.getAction())) {
+                what = MSG_LAUNCH;
+            }
+            Log.d(TAG, "received an action broadcast " + intent.getAction());
+            if (!TextUtils.isEmpty(key)) {
+                Log.d(TAG, "  on " + key);
+                Message.obtain(mHandler, what, key).sendToTarget();
+            }
+        }
+    };
+
+    Handler mHandler = new Handler() {
+        @Override
+        public void handleMessage(Message msg) {
+            Delta delta = null;
+            if (msg.obj instanceof Delta) {
+                delta = (Delta) msg.obj;
+            }
+            switch (msg.what) {
+                case MSG_NOTIFY:
+                    Log.i(TAG, "notify: " + delta.mSbn.getKey());
+                    synchronized (sNotifications) {
+                        int position = mOrderHelper.getIndex(delta.mSbn.getKey());
+                        if (position == -1) {
+                            sNotifications.add(delta.mSbn);
+                        } else {
+                            sNotifications.set(position, delta.mSbn);
+                        }
+                        mOrderHelper.updateKeyOrder(delta.mKeys);
+                        Collections.sort(sNotifications, mOrderHelper);
+                        Log.i(TAG, "finish with: " + sNotifications.size());
+                    }
+                    LocalBroadcastManager.getInstance(Listener.this)
+                            .sendBroadcast(new Intent(ACTION_REFRESH)
+                            .putExtra(EXTRA_KEY, delta.mSbn.getKey()));
+                    break;
+
+                case MSG_CANCEL:
+                    Log.i(TAG, "remove: " + delta.mSbn.getKey());
+                    synchronized (sNotifications) {
+                        int position = mOrderHelper.getIndex(delta.mSbn.getKey());
+                        if (position != -1) {
+                            sNotifications.remove(position);
+                        }
+                        mOrderHelper.updateKeyOrder(delta.mKeys);
+                        Collections.sort(sNotifications, mOrderHelper);
+                    }
+                    LocalBroadcastManager.getInstance(Listener.this)
+                            .sendBroadcast(new Intent(ACTION_REFRESH));
+                    break;
+
+                case MSG_ORDER:
+                    Log.i(TAG, "reorder");
+                    synchronized (sNotifications) {
+                        mOrderHelper.updateKeyOrder(delta.mKeys);
+                        Collections.sort(sNotifications, mOrderHelper);
+                    }
+                    LocalBroadcastManager.getInstance(Listener.this)
+                            .sendBroadcast(new Intent(ACTION_REFRESH));
+                    break;
+
+                case MSG_STARTUP:
+                    fetchActive();
+                    Log.i(TAG, "start with: " + sNotifications.size() + " notifications.");
+                    LocalBroadcastManager.getInstance(Listener.this)
+                            .sendBroadcast(new Intent(ACTION_REFRESH));
+                    break;
+
+                case MSG_DISMISS:
+                    if (msg.obj instanceof String) {
+                        final String key = (String) msg.obj;
+                        StatusBarNotification sbn = sNotifications.get(mOrderHelper.getIndex(key));
+                        if ((sbn.getNotification().flags & Notification.FLAG_AUTO_CANCEL) != 0 &&
+                                sbn.getNotification().contentIntent != null) {
+                            try {
+                                sbn.getNotification().contentIntent.send();
+                            } catch (PendingIntent.CanceledException e) {
+                                Log.d(TAG, "failed to send intent for " + sbn.getKey(), e);
+                            }
+                        }
+                        cancelNotification(key);
+                    }
+                    break;
+
+                case MSG_LAUNCH:
+                    if (msg.obj instanceof String) {
+                        final String key = (String) msg.obj;
+                        StatusBarNotification sbn = sNotifications.get(mOrderHelper.getIndex(key));
+                        if (sbn.getNotification().contentIntent != null) {
+                            try {
+                                sbn.getNotification().contentIntent.send();
+                            } catch (PendingIntent.CanceledException e) {
+                                Log.d(TAG, "failed to send intent for " + sbn.getKey(), e);
+                            }
+                        }
+                        if ((sbn.getNotification().flags & Notification.FLAG_AUTO_CANCEL) != 0) {
+                            cancelNotification(key);
+                        }
+                    }
+                    break;
+            }
+        }
+    };
+
+    @Override
+    public void onCreate() {
+        super.onCreate();
+        Log.d(TAG, "registering broadcast listener");
+        final IntentFilter intentFilter = new IntentFilter();
+        intentFilter.addAction(ACTION_DISMISS);
+        intentFilter.addAction(ACTION_LAUNCH);
+        LocalBroadcastManager.getInstance(this).registerReceiver(mBroadcastReceiver, intentFilter);
+    }
+
+    @Override
+    public void onDestroy() {
+        LocalBroadcastManager.getInstance(this).unregisterReceiver(mBroadcastReceiver);
+        super.onDestroy();
+    }
+
+    @Override
+    public void onListenerConnected(String[] notificationKeys) {
+        Message.obtain(mHandler, MSG_STARTUP).sendToTarget();
+    }
+
+    @Override
+    public void onNotificationOrderUpdate() {
+        Message.obtain(mHandler, MSG_ORDER,
+                new Delta(null, getOrderedNotificationKeys())).sendToTarget();
+    }
+
+    @Override
+    public void onNotificationPosted(StatusBarNotification sbn) {
+        Message.obtain(mHandler, MSG_NOTIFY,
+                new Delta(sbn, getOrderedNotificationKeys())).sendToTarget();
+    }
+
+    @Override
+    public void onNotificationRemoved(StatusBarNotification sbn) {
+        Message.obtain(mHandler, MSG_CANCEL,
+                new Delta(sbn, getOrderedNotificationKeys())).sendToTarget();
+    }
+
+    private void fetchActive() {
+        String[] keys = getOrderedNotificationKeys();
+        sNotifications = new ArrayList<StatusBarNotification>();
+        sNotifications.clear();
+        for (int i = 0; i < keys.length; i += PAGE) {
+            final int j = (i + PAGE < keys.length ? i + PAGE : keys.length);
+            String[] fetchKeys = Arrays.copyOfRange(keys, i, j);
+            StatusBarNotification[] sbns = getActiveNotifications(fetchKeys);
+            for(int s = 0; s < sbns.length; s++) {
+                // unfortunately cloneLight() is hidden
+                sNotifications.add(sbns[s]);
+            }
+        }
+        mOrderHelper = new OrderedNotificationsHelper(keys);
+        Collections.sort(sNotifications, mOrderHelper);
+    }
+}
diff --git a/NotificationListenerSample/src/com/android/example/notificationlistener/NotificationListenerActivity.java b/NotificationListenerSample/src/com/android/example/notificationlistener/NotificationListenerActivity.java
new file mode 100644
index 0000000..7699d33
--- /dev/null
+++ b/NotificationListenerSample/src/com/android/example/notificationlistener/NotificationListenerActivity.java
@@ -0,0 +1,260 @@
+/*
+ * Copyright (C) 2014 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.example.notificationlistener;
+
+import android.app.AlertDialog;
+import android.app.ListActivity;
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.DialogInterface;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.os.Bundle;
+import android.provider.Settings.Secure;
+import android.service.notification.StatusBarNotification;
+import android.support.v4.content.LocalBroadcastManager;
+import android.util.Log;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.BaseAdapter;
+import android.widget.Button;
+import android.widget.FrameLayout;
+import android.widget.TextView;
+
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+
+public class NotificationListenerActivity extends ListActivity {
+    private static final String LISTENER_PATH = "com.android.example.notificationlistener/" +
+            "com.android.example.notificationlistener.Listener";
+    private static final String TAG = "NotificationListenerActivity";
+
+    private Button mLaunchButton;
+    private TextView mEmptyText;
+    private StatusAdaptor mStatusAdaptor;
+    private final BroadcastReceiver mRefreshListener = new BroadcastReceiver() {
+        @Override
+        public void onReceive(Context context, Intent intent) {
+            Log.i(TAG, "update tickle");
+            updateList(intent.getStringExtra(Listener.EXTRA_KEY));
+        }
+    };
+
+    @Override
+    public void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setTitle(R.string.long_app_name);
+        setContentView(R.layout.main);
+        mLaunchButton = (Button) findViewById(R.id.launch_settings);
+        mEmptyText = (TextView) findViewById(android.R.id.empty);
+        mStatusAdaptor = new StatusAdaptor(this);
+        setListAdapter(mStatusAdaptor);
+    }
+
+    @Override
+    protected void onStop() {
+        LocalBroadcastManager.getInstance(this).unregisterReceiver(mRefreshListener);
+        super.onStop();
+    }
+
+    @Override
+    public void onStart() {
+        super.onStart();
+        final IntentFilter intentFilter = new IntentFilter(Listener.ACTION_REFRESH);
+        LocalBroadcastManager.getInstance(this).registerReceiver(mRefreshListener, intentFilter);
+        updateList(null);
+    }
+
+    @Override
+    public void onResume() {
+        super.onResume();
+        checkEnabled();
+    }
+
+    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
+        checkEnabled();
+    }
+
+    private void checkEnabled() {
+        String listeners = Secure.getString(getContentResolver(),
+                "enabled_notification_listeners");
+        if (listeners != null && listeners.contains(LISTENER_PATH)) {
+            mLaunchButton.setText(R.string.launch_to_disable);
+            mEmptyText.setText(R.string.waiting_for_content);
+        } else {
+            mLaunchButton.setText(R.string.launch_to_enable);
+            mEmptyText.setText(R.string.nothing_to_see);
+            AlertDialog.Builder builder = new AlertDialog.Builder(this);
+            builder.setMessage(R.string.explanation)
+                    .setTitle(R.string.disabled);
+            builder.setPositiveButton(R.string.enable_it, new DialogInterface.OnClickListener() {
+                public void onClick(DialogInterface dialog, int id) {
+                    launchSettings(null);
+                }
+            });
+            builder.setNegativeButton(R.string.cancel, null);
+            builder.create().show();
+        }
+    }
+
+    public void launchSettings(View v) {
+        startActivityForResult(
+                new Intent("android.settings.ACTION_NOTIFICATION_LISTENER_SETTINGS"), 0);
+    }
+
+    public void dismiss(View v) {
+        Log.d(TAG, "clicked dismiss ");
+        Object tag = v.getTag();
+        if (tag instanceof StatusBarNotification) {
+            StatusBarNotification sbn = (StatusBarNotification) tag;
+            Log.d(TAG, "  on " + sbn.getKey());
+            LocalBroadcastManager.getInstance(this).
+                    sendBroadcast(new Intent(Listener.ACTION_DISMISS)
+                            .putExtra(Listener.EXTRA_KEY, sbn.getKey()));
+        }
+    }
+
+    public void launch(View v) {
+        Log.d(TAG, "clicked launch");
+        Object tag = v.getTag();
+        if (tag instanceof StatusBarNotification) {
+            StatusBarNotification sbn = (StatusBarNotification) tag;
+            Log.d(TAG, "  on " + sbn.getKey());
+            LocalBroadcastManager.getInstance(this).
+                    sendBroadcast(new Intent(Listener.ACTION_LAUNCH)
+                            .putExtra(Listener.EXTRA_KEY, sbn.getKey()));
+        }
+    }
+
+    private void updateList(String key) {
+        if (mStatusAdaptor.requiresInitialization()) {
+            final List<StatusBarNotification> notifications = Listener.getNotifications();
+            if (notifications != null) {
+                mStatusAdaptor.init(notifications);
+            }
+        }
+        mStatusAdaptor.update(key);
+    }
+
+    private class StatusAdaptor extends BaseAdapter {
+        private final Context mContext;
+        private List<StatusBarNotification> mNotifications;
+        private HashMap<String, Long> mKeyToId;
+        private HashSet<String> mKeys;
+        private long mNextId;
+        private HashMap<String, View> mRecycledViews;
+        private String mUpdateKey;
+
+        public StatusAdaptor(Context context) {
+            mContext = context;
+            mKeyToId = new HashMap<String, Long>();
+            mKeys = new HashSet<String>();
+            mNextId = 0;
+            mRecycledViews = new HashMap<String, View>();
+        }
+
+        @Override
+        public int getCount() {
+            return mNotifications == null ? 0 : mNotifications.size();
+        }
+
+        @Override
+        public Object getItem(int position) {
+            return mNotifications.get(position);
+        }
+
+        @Override
+        public boolean hasStableIds() {
+            return true;
+        }
+
+        @Override
+        public long getItemId(int position) {
+            final StatusBarNotification sbn = mNotifications.get(position);
+            final String key = sbn.getKey();
+            if (!mKeyToId.containsKey(key)) {
+                mKeyToId.put(key, mNextId);
+                mNextId ++;
+            }
+            return mKeyToId.get(key);
+        }
+
+        @Override
+        public View getView(int position, View view, ViewGroup list) {
+            if (view == null) {
+                view = View.inflate(mContext, R.layout.item, null);
+            }
+            FrameLayout container = (FrameLayout) view.findViewById(R.id.remote_view);
+            View dismiss = view.findViewById(R.id.dismiss);
+            StatusBarNotification sbn = mNotifications.get(position);
+            View child;
+            if (container.getTag() instanceof StatusBarNotification &&
+                    container.getChildCount() > 0) {
+                // recycle the view
+                StatusBarNotification old = (StatusBarNotification) container.getTag();
+                if (sbn.getKey().equals(mUpdateKey)) {
+                    //this view is out of date, discard it
+                    mUpdateKey = null;
+                } else {
+                    View content = container.getChildAt(0);
+                    container.removeView(content);
+                    mRecycledViews.put(old.getKey(), content);
+                }
+            }
+            child = mRecycledViews.get(sbn.getKey());
+            if (child == null) {
+                child = sbn.getNotification().contentView.apply(mContext, null);
+            }
+            container.setTag(sbn);
+            container.removeAllViews();
+            container.addView(child);
+            dismiss.setVisibility(sbn.isClearable() ? View.VISIBLE : View.GONE);
+            dismiss.setTag(sbn);
+            return view;
+        }
+
+        public void update(String key) {
+            if (mNotifications != null) {
+                synchronized (mNotifications) {
+                    mKeys.clear();
+                    for (int i = 0; i < mNotifications.size(); i++) {
+                        mKeys.add(mNotifications.get(i).getKey());
+                    }
+                    mKeyToId.keySet().retainAll(mKeys);
+                }
+                if (key == null) {
+                    mRecycledViews.clear();
+                } else {
+                    mUpdateKey = key;
+                    mRecycledViews.remove(key);
+                }
+                Log.d(TAG, "notifyDataSetChanged");
+                notifyDataSetChanged();
+            } else {
+                Log.d(TAG, "missed and update");
+            }
+        }
+
+        public boolean requiresInitialization() {
+            return mNotifications == null;
+        }
+
+        public void init(List<StatusBarNotification> notifications) {
+            mNotifications = notifications;
+        }
+    }
+}
diff --git a/NotificationListenerSample/src/com/android/example/notificationlistener/OrderedNotificationsHelper.java b/NotificationListenerSample/src/com/android/example/notificationlistener/OrderedNotificationsHelper.java
new file mode 100644
index 0000000..789f052
--- /dev/null
+++ b/NotificationListenerSample/src/com/android/example/notificationlistener/OrderedNotificationsHelper.java
@@ -0,0 +1,94 @@
+/*
+ * Copyright (C) 2014 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.example.notificationlistener;
+
+import android.service.notification.StatusBarNotification;
+
+import java.util.Comparator;
+import java.util.HashMap;
+
+/**
+ * A {@link java.util.Comparator} that will sort notifications into the proper display order.
+ */
+public class OrderedNotificationsHelper implements Comparator<StatusBarNotification> {
+    private HashMap<String, Integer> rankCache;
+    private String[] mOrderedKeys;
+
+    public OrderedNotificationsHelper(String[] notificationOrder) {
+        this.rankCache = new HashMap<String, Integer>();
+        mOrderedKeys = notificationOrder;
+    }
+
+    public String[] getOrderedKeys() {
+        return mOrderedKeys;
+    }
+
+    public int getIndex(String key) {
+        if (rankCache.isEmpty()) {
+            fillCache();
+        }
+        Integer rank = rankCache.get(key);
+        return rank == null ? -1 : rank;
+    }
+
+    /**
+     * Update the order impleneted by {@link #compare(Object, Object)}.
+     * @param orderedKeys notification keys in order from
+     * {@link android.service.notification.NotificationListenerService#getOrderedNotificationKeys()}
+     */
+    public void updateKeyOrder(String[] orderedKeys) {
+        // TODO implement incremental updates
+        // Defer as much work as possible to fillCache()
+        mOrderedKeys = orderedKeys;
+        rankCache.clear();
+    }
+
+    private void fillCache() {
+        final int N = mOrderedKeys.length;
+        for (int i = 0; i < N; i++) {
+            rankCache.put(mOrderedKeys[i], i);
+        }
+    }
+
+    /**
+     * More important notifications will sort to the front
+     *
+     * @param lhs an {@code Object}.
+     * @param rhs a second {@code Object} to compare with {@code lhs}.
+     * @return 0 if lhs and rhs are of equal importance, less than 0 if lhs more
+     *      important that rhs, and greater than 0 if lhs less important than rhs.
+     */
+    public int compare(StatusBarNotification lhs, StatusBarNotification rhs) {
+        if (rankCache.isEmpty()) {
+            fillCache();
+        }
+        if (lhs == null || rhs == null) {
+            throw new IllegalArgumentException("passed null to the Comparator");
+        }
+        final Integer lIndex = rankCache.get(lhs.getKey());
+        final Integer rIndex = rankCache.get(rhs.getKey());
+        if (rIndex == null && rIndex == null) {
+            return 0;
+        }
+        if (lIndex == null) {
+            return 1; // down sort unknown notification
+        }
+        if (rIndex == -1) {
+            return -1; // down sort unknown notification
+        }
+        return Integer.compare(lIndex, rIndex);
+    }
+}
\ No newline at end of file