Repeating alarms : Android tutorial

Program description:

This program will demo how to create repeating alarms, which will trigger broadcast receivers.

This program has one activity with one button, and a broadcast receiver.
On clicking the button we will set an alarm which will trigger after 5 seconds from now.
That alarm will keep repeating for every next 5 seconds. Every time it triggers it will send a broadcast receiver. Broadcast receiver will print "got" message for every 5 seconds.

Before using this program, you should know  how to create alarms with broadcast receiver.

First Activity

package com.techpalle.b15_alarm_asg1;

import java.util.List;

import android.os.Bundle;
import android.app.Activity;
import android.app.ActivityManager;
import android.app.AlarmManager;
import android.app.PendingIntent;
import android.app.ActivityManager.RunningTaskInfo;
import android.content.Context;
import android.content.Intent;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class MainActivity extends Activity {
 AlarmManager am;
 Button b;
 ActivityManager acm;
 
 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.activity_main);
 acm = (ActivityManager) getSystemService(Context.ACTIVITY_SERVICE);
 List l = acm.getRunningTasks(10);

 b = (Button) findViewById(R.id.button1);
 am = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
 b.setOnClickListener(new OnClickListener() {
 @Override
 public void onClick(View v) {
 Intent in = new Intent();
 in.setAction("com.techpalle.action.ALARM_REPEAT");
 PendingIntent pi = PendingIntent.getBroadcast(
 getApplicationContext(),
 0, in, 0);
 am.setRepeating(AlarmManager.RTC_WAKEUP, 
 System.currentTimeMillis()+5000,
 5000, 
 pi);
 }
 });
 }

 @Override
 public boolean onCreateOptionsMenu(Menu menu) {
 // Inflate the menu; this adds items to the action bar if it is present.
 getMenuInflater().inflate(R.menu.main, menu);
 return true;
 }

}

Broadcast receiver 
File name : AlarmRecvr.java

package com.techpalle.b15_alarm_asg1;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.widget.Toast;

public class AlarmRecvr extends BroadcastReceiver {

 @Override
 public void onReceive(Context context, Intent intent) {
 // TODO Auto-generated method stub
 Toast.makeText(context, "got", 0).show();
 }

}

xml file for first activity 
File name : activity_main.xml

  xmlns:tools="http://schemas.android.com/tools" 
 android:layout_width="match_parent" 
 android:layout_height="match_parent" 
 android:paddingBottom="@dimen/activity_vertical_margin" 
 android:paddingLeft="@dimen/activity_horizontal_margin" 
 android:paddingRight="@dimen/activity_horizontal_margin" 
 android:paddingTop="@dimen/activity_vertical_margin" 
 tools:context=".MainActivity" > 
  android:id="@+id/textView1" 
 android:layout_width="wrap_content" 
 android:layout_height="wrap_content" 
 android:text="@string/hello_world" /> 
 

Manifest file
File name : AndroidManifest.xml

  
  package="com.techpalle.b15_alarm_asg1" 
 android:versionCode="1" 
 android:versionName="1.0" > 
  android:minSdkVersion="8" 
 android:targetSdkVersion="17" /> 
  android:allowBackup="true" 
 android:icon="@drawable/ic_launcher" 
 android:label="@string/app_name" 
 android:theme="@style/AppTheme" > 
  android:name="com.techpalle.b15_alarm_asg1.MainActivity" 
 android:label="@string/app_name"> 
  
  
  
  
  
  
  
  
  
  
  
  

hi

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