A simple example of Alarm Service, using AlarmManager

Alarm Service in Android

AlarmManager class provides access to the system alarm services. These allow you to schedule your application to be run at some point in the future. When an alarm goes off, the Intent that had been registered for it is broadcast by the system, automatically starting the target application if it is not already running. 

In this exercise, a scheduled alarm of 10 seconds will start a service, MyAlarmService. 

Modify main.xml to have two button to start and cancel the alarm.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello"
/>
<Button
android:id="@+id/startalarm"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Start"
/>

<Button
android:id="@+id/cancelalarm"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Cancel"
/>

</LinearLayout>