Updating sample to use notification groups and summaries for Android N.

Change-Id: Icf4cfcb19aeab7bcecc651410e1643068d5736d8

3 files changed, 119 insertions, 56 deletions

diff --git a/notification/ActiveNotifications/Application/src/main/java/com/example/android/activenotifications/ActiveNotificationFragment.java b/notification/ActiveNotifications/Application/src/main/java/com/example/android/activenotifications/ActiveNotificationFragment.java
index 3e87849a..7753b371 100644
--- a/notification/ActiveNotifications/Application/src/main/java/com/example/android/activenotifications/ActiveNotificationFragment.java
+++ b/notification/ActiveNotifications/Application/src/main/java/com/example/android/activenotifications/ActiveNotificationFragment.java
@@ -23,6 +23,7 @@ import android.content.Intent;
 import android.os.Bundle;
 import android.service.notification.StatusBarNotification;
 import android.support.v4.app.Fragment;
+import android.support.v4.app.NotificationCompat;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
@@ -31,17 +32,31 @@ import android.widget.TextView;
 import com.example.android.common.logger.Log;
 
 /**
- * A fragment that enables display of notifications.
+ * A fragment that allows notifications to be enqueued.
  */
 public class ActiveNotificationFragment extends Fragment {
 
+    /**
+     * The request code can be any number as long as it doesn't match another request code used
+     * in the same app.
+     */
+    private static final int REQUEST_CODE = 2323;
+
     private static final String TAG = "ActiveNotificationFragment";
 
+    private static final String NOTIFICATION_GROUP =
+            "com.example.android.activenotifications.notification_type";
+
+    private static final int NOTIFICATION_GROUP_SUMMARY_ID = 1;
+
     private NotificationManager mNotificationManager;
+
     private TextView mNumberOfNotifications;
 
-    // Every notification needs a unique ID otherwise the previous one would be overwritten.
-    private int mNotificationId = 0;
+    // Every notification needs a unique ID otherwise the previous one would be overwritten. This
+    // variable is incremented when used.
+    private static int sNotificationId = NOTIFICATION_GROUP_SUMMARY_ID + 1;
+
     private PendingIntent mDeletePendingIntent;
 
     @Override
@@ -69,7 +84,7 @@ public class ActiveNotificationFragment extends Fragment {
             public void onClick(View v) {
                 switch (v.getId()) {
                     case R.id.add_notification: {
-                        addNotificationAndReadNumber();
+                        addNotificationAndUpdateSummaries();
                         break;
                     }
                 }
@@ -81,33 +96,72 @@ public class ActiveNotificationFragment extends Fragment {
         // Create a PendingIntent to be fired upon deletion of a Notification.
         Intent deleteIntent = new Intent(ActiveNotificationActivity.ACTION_NOTIFICATION_DELETE);
         mDeletePendingIntent = PendingIntent.getBroadcast(getActivity(),
-                2323 /* requestCode */, deleteIntent, 0);
+                REQUEST_CODE, deleteIntent, 0);
         // [END create_pending_intent_for_deletion]
     }
 
     /**
-     * Add a new {@link Notification} with sample data and send it to the system.
-     * Then read the current number of displayed notifications for this application.
+     * Adds a new {@link Notification} with sample data and sends it to the system.
+     * Then updates the current number of displayed notifications for this application and
+     * creates a notification summary if more than one notification exists.
      */
-    private void addNotificationAndReadNumber() {
+    private void addNotificationAndUpdateSummaries() {
         // [BEGIN create_notification]
         // Create a Notification and notify the system.
-        final Notification.Builder builder = new Notification.Builder(getActivity())
+        final NotificationCompat.Builder builder = new NotificationCompat.Builder(getActivity())
                 .setSmallIcon(R.mipmap.ic_notification)
                 .setContentTitle(getString(R.string.app_name))
                 .setContentText(getString(R.string.sample_notification_content))
                 .setAutoCancel(true)
-                .setDeleteIntent(mDeletePendingIntent);
+                .setDeleteIntent(mDeletePendingIntent)
+                .setGroup(NOTIFICATION_GROUP);
 
         final Notification notification = builder.build();
-        mNotificationManager.notify(++mNotificationId, notification);
+        mNotificationManager.notify(getNewNotificationId(), notification);
         // [END create_notification]
         Log.i(TAG, "Add a notification");
+
+        updateNotificationSummary();
         updateNumberOfNotifications();
     }
 
     /**
-     * Request the current number of notifications from the {@link NotificationManager} and
+     * Adds/updates/removes the notification summary as necessary.
+     */
+    protected void updateNotificationSummary() {
+        final StatusBarNotification[] activeNotifications = mNotificationManager
+                .getActiveNotifications();
+
+        int numberOfNotifications = activeNotifications.length;
+        // Since the notifications might include a summary notification remove it from the count if
+        // it is present.
+        for (StatusBarNotification notification : activeNotifications) {
+          if (notification.getId() == NOTIFICATION_GROUP_SUMMARY_ID) {
+            numberOfNotifications--;
+            break;
+          }
+        }
+
+        if (numberOfNotifications > 1) {
+            // Add/update the notification summary.
+            String notificationContent = getString(R.string.sample_notification_summary_content,
+                    "" + numberOfNotifications);
+            final NotificationCompat.Builder builder = new NotificationCompat.Builder(getActivity())
+                    .setSmallIcon(R.mipmap.ic_notification)
+                    .setStyle(new NotificationCompat.BigTextStyle()
+                            .setSummaryText(notificationContent))
+                    .setGroup(NOTIFICATION_GROUP)
+                    .setGroupSummary(true);
+            final Notification notification = builder.build();
+            mNotificationManager.notify(NOTIFICATION_GROUP_SUMMARY_ID, notification);
+        } else {
+            // Remove the notification summary.
+            mNotificationManager.cancel(NOTIFICATION_GROUP_SUMMARY_ID);
+        }
+    }
+
+    /**
+     * Requests the current number of notifications from the {@link NotificationManager} and
      * display them to the user.
      */
     protected void updateNumberOfNotifications() {
@@ -121,4 +175,19 @@ public class ActiveNotificationFragment extends Fragment {
                 numberOfNotifications));
         Log.i(TAG, getString(R.string.active_notifications, numberOfNotifications));
     }
+
+    /**
+     * Retrieves a unique notification ID.
+     */
+    public int getNewNotificationId() {
+        int notificationId = sNotificationId++;
+
+        // Unlikely in the sample, but the int will overflow if used enough so we skip the summary
+        // ID. Most apps will prefer a more deterministic way of identifying an ID such as hashing
+        // the content of the notification.
+        if (notificationId == NOTIFICATION_GROUP_SUMMARY_ID) {
+            notificationId = sNotificationId++;
+        }
+        return notificationId;
+    }
 }
diff --git a/notification/ActiveNotifications/Application/src/main/res/values/strings.xml b/notification/ActiveNotifications/Application/src/main/res/values/strings.xml
index 0f2977d1..a4275fdf 100644
--- a/notification/ActiveNotifications/Application/src/main/res/values/strings.xml
+++ b/notification/ActiveNotifications/Application/src/main/res/values/strings.xml
@@ -19,4 +19,5 @@
  <string name="active_notifications">Active Notifications: %1$s</string>
  <string name="update_notification_count">Update count</string>
  <string name="sample_notification_content">This is a sample notification.</string>
+ <string name="sample_notification_summary_content">There are %s ActiveNotifications.</string>
 </resources>
diff --git a/notification/ActiveNotifications/template-params.xml b/notification/ActiveNotifications/template-params.xml
index 65fefd48..a4117c7c 100644
--- a/notification/ActiveNotifications/template-params.xml
+++ b/notification/ActiveNotifications/template-params.xml
@@ -16,57 +16,39 @@
 -->
 <sample>
     <name>ActiveNotification</name>
-    <group>Notification</group>  <!-- This field will be deprecated in the future
-                            and replaced with the "categories" tags below. -->
+    <group>Android N Preview</group>
     <package>com.example.android.activenotifications</package>
 
-    <minSdk>23</minSdk>
-
-    <!-- Include additional dependencies here.-->
-    <!-- dependency>com.google.android.gms:play-services:5.0.+</dependency -->
+    <minSdk>"N"</minSdk>
+    <targetSdkVersion>"N"</targetSdkVersion>
+    <compileSdkVersion>"android-N"</compileSdkVersion>
 
     <strings>
         <intro>
             <![CDATA[
-The NotificationManager can tell you how many notifications your application is currently showing.
-This sample demonstrates how to use this API that has been introduced with Android M.
-To get started, press the "add a notification" button.
-When a notification is being canceled, the count gets updated via a PendingIntent.
+Notifications can now be grouped in Android N. Since Android M, the
+NotificationManager can tell you how many notifications your application 
+is currently showing. This sample demonstrates how to use these APIs 
+together for a nicer user experience when an app may have multiple 
+notifications. To get started, press the "add a notification" button. 
+If you add more than one notification a notification summary will be 
+added. When a notification is being canceled, the count gets updated 
+via a PendingIntent.
             ]]>
         </intro>
     </strings>
 
-    <!-- The basic templates have already been enabled. Uncomment more as desired. -->
     <template src="base" />
     <template src="FragmentView" />
     <common src="activities" />
     <common src="logger" />
 
     <metadata>
-        <!-- Values: {DRAFT | PUBLISHED | INTERNAL | DEPRECATED | SUPERCEDED} -->
         <status>DRAFT</status>
-        <!-- See http://go/sample-categories for details on the next 4 fields. -->
-        <!-- Most samples just need to udpate the Categories field. This is a comma-
-             seperated list of topic tags. Unlike the old category system, samples
-             may have multiple categories, so feel free to add extras. Try to avoid
-             simply tagging everything with "UI". :)-->
-        <categories>Getting Started, Notification</categories>
+        <categories>Getting Started, Notification, Android N Preview</categories>
         <technologies>Android</technologies>
         <languages>Java</languages>
         <solutions>Mobile</solutions>
-        <!-- Values: {BEGINNER | INTERMEDIATE | ADVANCED | EXPERT} -->
-        <!-- Beginner is for "getting started" type content, or essential content.
-             (e.g. "Hello World", activities, intents)
-
-             Intermediate is for content that covers material a beginner doesn't need
-             to know, but that a skilled developer is expected to know.
-             (e.g. services, basic styles and theming, sync adapters)
-
-             Advanced is for highly technical content geared towards experienced developers.
-             (e.g. performance optimizations, custom views, bluetooth)
-
-             Expert is reserved for highly technical or specialized content, and should
-             be used sparingly. (e.g. VPN clients, SELinux, custom instrumentation runners) -->
         <level>INTERMEDIATE</level>
         <icon>screenshots/icon-web.png</icon>
         <screenshots>
@@ -78,22 +60,33 @@ When a notification is being canceled, the count gets updated via a PendingInten
             <android>android.app.NotificationManager</android>
         </api_refs>
         <description>
-            The NotificationManager can tell you how many notifications your application is
-            currently showing. This sample demonstrates how to use this API that has been
-            introduced with Android M.
-         </description>
+<![CDATA[
+Notification Groups and the Notification Manager can be used together to simplify
+how users experience notifications. This sample demonstrates how
+the NotificationManager can tell you how many notifications your
+application is currently showing. It also shows how to manage the
+notifications as a group and introduce a summary for the group, when
+supported by the platform.
+]]>
+        </description>
         <intro>
-            The [NotificationManager][1] has become more powerful.
-            Starting with Android M, you can query it for the active notifications that
-            your app sent using the [notify][2] methods.
+<![CDATA[
+Notifications can now be grouped.
+
+Starting with Android N, you can set notification groups for notifications
+and define a notification group summary.
+
+Starting with Android M, you can query it for the active notifications that
+your app sent using the [notify][2] methods.
 
-            This sample demonstrates simple use of this newly added functionality by
-            allowing a user to add notifications and then querying how many notifications
-            are currently being displayed via the [getActiveNotifications()][3] method.
+This sample demonstrates simple use of these features by allowing a user 
+to add notifications and then query how many notifications
+are currently being displayed via the [getActiveNotifications()][3] method.
 
-            [1]: https://developer.android.com/reference/android/app/NotificationManager.html
-            [2]: https://developer.android.com/reference/android/app/NotificationManager.html#notify(int, android.app.Notification)
-            [2]: https://developer.android.com/reference/android/app/NotificationManager.html#getActiveNotifications()
+[1]: https://developer.android.com/reference/android/app/NotificationManager.html
+[2]: https://developer.android.com/reference/android/app/NotificationManager.html#notify(int, android.app.Notification)
+[3]: https://developer.android.com/reference/android/app/NotificationManager.html#getActiveNotifications()
+]]>
         </intro>
     </metadata>
 </sample>