android-Building a Notification,Preserving Navigation when Starting an Activity

  NotificationCompat.Builder is in the Support Library. You should use NotificationCompat and its subclasses, particularly NotificationCompat.Builder, to provide the best notification support for a wide range of platforms.

 >When creating a notification, specify the UI content and actions with a NotificationCompat.Builder object. At bare minimum, a Builder object must include the following:

• A small icon, set by setSmallIcon()
• A title, set by setContentTitle()
• Detail text, set by setContentText()

NotificationCompat.Builder mBuilder =
    new NotificationCompat.Builder(this)
    .setSmallIcon(R.drawable.notification_icon)
    .setContentTitle("My notification")
    .setContentText("Hello World!");

Intent resultIntent = new Intent(this, ResultActivity.class);
...
// Because clicking the notification opens a new ("special") activity, there's
// no need to create an artificial back stack.
PendingIntent resultPendingIntent =
    PendingIntent.getActivity(
    this,
    0,
    resultIntent,
    PendingIntent.FLAG_UPDATE_CURRENT
);

To issue the notification:

• Get an instance of NotificationManager.
• Use the notify() method to issue the notification. When you call notify(), specify a notification ID. You can use this ID to update the notification later on. This is described in more detail in Managing Notifications.
• Call build(), which returns a Notification object containing your specifications.

  For example:

  NotificationCompat.Builder mBuilder;
  ...
  // Sets an ID for the notification
  int mNotificationId = 001;
  // Gets an instance of the NotificationManager service
  NotificationManager mNotifyMgr = 
          (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
  // Builds the notification and issues it.
  mNotifyMgr.notify(mNotificationId, mBuilder.build());

> Preserving Navigation when Starting an Activity

Part of designing a notification is preserving the user's expected navigation experience. For a detailed discussion of this topic, see the Notifications API guide. There are two general situations:

Regular activity

You're starting an Activity that's part of the application's normal workflow.

Special activity

The user only sees this Activity if it's started from a notification. In a sense, the Activity extends the notification by providing information that would be hard to display in the notification itself.

Intent resultIntent = new Intent(this, ResultActivity.class);
TaskStackBuilder stackBuilder = TaskStackBuilder.create(this);
// Adds the back stack
stackBuilder.addParentStack(ResultActivity.class);
// Adds the Intent to the top of the stack
stackBuilder.addNextIntent(resultIntent);
// Gets a PendingIntent containing the entire back stack
PendingIntent resultPendingIntent =
        stackBuilder.getPendingIntent(0, PendingIntent.FLAG_UPDATE_CURRENT);
...
NotificationCompat.Builder builder = new NotificationCompat.Builder(this);
builder.setContentIntent(resultPendingIntent);
NotificationManager mNotificationManager =
    (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
mNotificationManager.notify(id, builder.build());

 A special Activity doesn't need a back stack, so you don't have to define its Activity hierarchy in the manifest, and you don't have to call addParentStack() to build a back stack. Instead, use the manifest to set up the Activity task options, and create the PendingIntent by calling getActivity()

android:name="activityclass"

The activity's fully-qualified class name.

android:taskAffinity=""

Combined with the FLAG_ACTIVITY_NEW_TASK flag that you set in code, this ensures that thisActivity doesn't go into the application's default task. Any existing tasks that have the application's default affinity are not affected.

android:excludeFromRecents="true"

Excludes the new task from Recents, so that the user can't accidentally navigate back to it.

This snippet shows the element:

<activity
    android:name=".ResultActivity"
...
    android:launchMode="singleTask"
    android:taskAffinity=""
    android:excludeFromRecents="true">
</activity>

>Build and issue the notification:

1. Create an Intent that starts the Activity.
2. Set the Activity to start in a new, empty task by calling setFlags() with the flagsFLAG_ACTIVITY_NEW_TASK and FLAG_ACTIVITY_CLEAR_TASK.
3. Set any other options you need for the Intent.
4. Create a PendingIntent from the Intent by calling getActivity(). You can then use thisPendingIntent as the argument to setContentIntent().

// Instantiate a Builder object.
NotificationCompat.Builder builder = new NotificationCompat.Builder(this);
// Creates an Intent for the Activity
Intent notifyIntent =
        new Intent(new ComponentName(this, ResultActivity.class));
// Sets the Activity to start in a new, empty task
notifyIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | 
        Intent.FLAG_ACTIVITY_CLEAR_TASK);
// Creates the PendingIntent
PendingIntent notifyIntent =
        PendingIntent.getActivity(
        this,
        0,
        notifyIntent,
        PendingIntent.FLAG_UPDATE_CURRENT
);

// Puts the PendingIntent into the notification builder
builder.setContentIntent(notifyIntent);
// Notifications are issued by sending them to the
// NotificationManager system service.
NotificationManager mNotificationManager =
    (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
// Builds an anonymous Notification object from the builder, and
// passes it to the NotificationManager
mNotificationManager.notify(id, builder.build());