Scheduling background task using Alarm Manager Android

All of us know, what Alarm does. Alarms will run in the background, whenever it counter the time, plays nice Music. Alarm wake-up us. Every phone has this feature from low end to high end mobiles.

In Android, we can use Alarms to schedule the tasks. Android has Alarm manager to manage these Alarms.

Service, perform long-running operations in the background and does not provide a user interface.

We need to use Alarm manger as well as service for scheduling background task like downloading information at particular time.

Steps to Create background task :

1. Create project, specify default activity. The following code to set schedule and cancel schedule for background task

public void btnStartSchedule(View v) {

  try {
   AlarmManager alarms = (AlarmManager) this
     .getSystemService(Context.ALARM_SERVICE);

   Intent intent = new Intent(getApplicationContext(),
     AlaramReceiver.class);
   intent.putExtra(AlaramReceiver.ACTION_ALARM,
     AlaramReceiver.ACTION_ALARM);

   final PendingIntent pIntent = PendingIntent.getBroadcast(this,
     1234567, intent, PendingIntent.FLAG_UPDATE_CURRENT);

   alarms.setRepeating(AlarmManager.RTC_WAKEUP,
     System.currentTimeMillis(), 10000, pIntent);
   
   toast("Started...");
  } catch (Exception e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }

 }

 public void btnCancelSchedules(View v) {

  Intent intent = new Intent(getApplicationContext(),
    AlaramReceiver.class);
  intent.putExtra(AlaramReceiver.ACTION_ALARM,
    AlaramReceiver.ACTION_ALARM);

  final PendingIntent pIntent = PendingIntent.getBroadcast(this, 1234567,
    intent, PendingIntent.FLAG_UPDATE_CURRENT);

  AlarmManager alarms = (AlarmManager) this
    .getSystemService(Context.ALARM_SERVICE);

  alarms.cancel(pIntent);
  toast("Canceled...");
 }

2. Create AlarmReceiver, for waking up the task

public static String ACTION_ALARM = "com.alarammanager.alaram";

 @Override
 public void onReceive(Context context, Intent intent) {
  
  Log.i("Alarm Receiver", "Entered");
  Toast.makeText(context, "Entered", Toast.LENGTH_SHORT).show();
  
  Bundle bundle = intent.getExtras();
  String action = bundle.getString(ACTION_ALARM);
  if (action.equals(ACTION_ALARM)) {
 Log.i("Alarm Receiver", "If loop");
 Intent inService = new Intent(context,TaskService.class);
 context.startService(inService);
  }
  else
  {
 Log.i("Alarm Receiver", "Else loop");
 Toast.makeText(context, "Else loop", Toast.LENGTH_SHORT).show();
  }
 }

3. Create a Service do background task

public class TaskService extends IntentService {

 public TaskService() {
  super("TaskService");
  // TODO Auto-generated constructor stub
 }

 @Override
 protected void onHandleIntent(Intent arg0) {
  
  // Do some task
Log.i("TaskService","Service running");
 }

}

4. Specify the receiver and service in the Manifest file.

<application
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name" >
        <activity
            android:name=".AlaramScheduleActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

        <receiver
            android:name="AlaramReceiver"
            android:process=":remote" >
        </receiver>

        <service android:name=".TaskService" >
        </service>
    </application>

References : download_source_code