Handling alarms with Services

Just like starting Activities, starting a Service from an alarm involves scheduling an appropriate PendingIntent instance, this time using the static getService method:

Intent intent = new Intent(this,SMSDispatcherIntentService.class);
intent.putExtra(SMSDispatcherIntentService.TO_KEY, phoneNumber);
intent.putExtra(SMSDispatcherIntentService.TEXT_KEY, text);
PendingIntent service = PendingIntent.getService(
   context, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);
am.set(AlarmManager.RTC_WAKEUP, time, service);

As you already know, the Service should be globally defined on the Android Manifest with a service element. Given that we are calling it explicitly using the class name, we only need to define the service class:

<service android:name=".chapter6.SMSDispatcherIntentService" >
</service>

We almost certainly want our Service to do its work off the main thread, so sending work to an IntentService this way seems ideal, and an IntentService will also...