Sticky broadcast receiver assignment: android tutorial

Program description:

This is an assignment program on using sticky broadcast receiver. This assignment has 2 applications. 
First application will be having one activity with one button. This activity also has a dynamic receiver which will be registered on clicking that button. 
Second application is also having one activity with one button. A sticky broadcast will be fired on clicking that button.

First user will open second application and clicks on the button to send a sticky broadcast to send a broadcast with action "com.techpalle.action.STICKY".

Then user will open first application's activity and click the button to register for receiver for an action "com.techpalle.action.STICKY". Once user clicks on the button to register dynamic receiver with an action which was previously broadcasted by second application, android will immediately call the onReceive() method of the current application's dynamic receiver. Reason for this is, sticky broadcasts will stick with android for future users.

Wanted to know more about what exactly is a sticky broadcast?

First Application's First activity:

package com.techpalle.b15_rcvr_asg1;

import android.os.Bundle;
import android.app.Activity;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;

public class MainActivity extends Activity {

 private BroadcastReceiver br = new BroadcastReceiver() {
  @Override
  public void onReceive(Context context, Intent intent) {
   Toast.makeText(context, "Triggered..", 0).show();   
  }
 };
 private IntentFilter inf;
 Button b;
 
 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);
  inf = new IntentFilter();
  inf.addAction("com.techpalle.action.STICKY");
  
  b = (Button) findViewById(R.id.button1);
  b.setOnClickListener(new OnClickListener() {
   @Override
   public void onClick(View v) {
    registerReceiver(br, inf);
   }
  });
 }
 
 @Override
 protected void onDestroy() {
  unregisterReceiver(br);
  super.onDestroy();
 }

}

xml file for first activity 
File name : activity_main.xml

 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"  
   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" >  
   <Button  
     android:id="@+id/button1"  
     android:layout_width="wrap_content"  
     android:layout_height="wrap_content"  
     android:layout_alignParentLeft="true"  
     android:layout_alignParentTop="true"  
     android:layout_marginLeft="33dp"  
     android:layout_marginTop="28dp"  
     android:text="Register Receiver" />  
 </RelativeLayout>  

Manifest file
File name : AndroidManifest.xml

 <?xml version="1.0" encoding="utf-8"?>  
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"  
   package="com.techpalle.b15_rcvr_asg1"  
   android:versionCode="1"  
   android:versionName="1.0" >  
   <uses-sdk  
     android:minSdkVersion="8"  
     android:targetSdkVersion="17" />  
   <application  
     android:allowBackup="true"  
     android:icon="@drawable/ic_launcher"  
     android:label="@string/app_name"  
     android:theme="@style/AppTheme" >  
     <activity  
       android:name="com.techpalle.b15_rcvr_asg1.MainActivity"  
       android:label="@string/app_name" >  
       <intent-filter>  
         <action android:name="android.intent.action.MAIN" />  
         <category android:name="android.intent.category.LAUNCHER" />  
       </intent-filter>  
     </activity>  
   </application>  
 </manifest>  

Second Application's First activity:

package com.techpalle.b15_rcvr_asg1_app2;

import android.os.Bundle;
import android.app.Activity;
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 {
 Button b;
 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);
  b = (Button) findViewById(R.id.button1);
  b.setOnClickListener(new OnClickListener() {
   @Override
   public void onClick(View v) {
    Intent in = new Intent();
    in.setAction("com.techpalle.action.STICKY");
    sendStickyBroadcast(in);
   }
  });
 }

}

xml file for first activity (second application)
File name : activity_main.xml

 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"  
   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" >  
   <TextView  
     android:id="@+id/textView1"  
     android:layout_width="wrap_content"  
     android:layout_height="wrap_content"  
     android:text="@string/hello_world" />  
   <Button  
     android:id="@+id/button1"  
     android:layout_width="wrap_content"  
     android:layout_height="wrap_content"  
     android:layout_alignLeft="@+id/textView1"  
     android:layout_below="@+id/textView1"  
     android:layout_marginLeft="53dp"  
     android:layout_marginTop="21dp"  
     android:text="Send Sticky Broadcast" />  
 </RelativeLayout>  

Manifest file (for second application)
File name : AndroidManifest.xml

 <?xml version="1.0" encoding="utf-8"?>  
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"  
   package="com.techpalle.b15_rcvr_asg1_app2"  
   android:versionCode="1"  
   android:versionName="1.0" >  
   <uses-sdk  
     android:minSdkVersion="8"  
     android:targetSdkVersion="17" />  
   <application  
     android:allowBackup="true"  
     android:icon="@drawable/ic_launcher"  
     android:label="@string/app_name"  
     android:theme="@style/AppTheme" >  
     <activity  
       android:name="com.techpalle.b15_rcvr_asg1_app2.MainActivity"  
       android:label="@string/app_name" >  
       <intent-filter>  
         <action android:name="android.intent.action.MAIN" />  
         <category android:name="android.intent.category.LAUNCHER" />  
       </intent-filter>  
     </activity>  
   </application>  
 <uses-permission android:name="android.permission.BROADCAST_STICKY"/>  
 </manifest>  

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Android Interview questions related to Sticky broadcast receivers:
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Difference between Intent, Sticky Intent, and Pending Intent?

Tags: android, sticky broadcast, receivers, sticky, dynamic receivers, sticky intent, permission, BROADCAST_STICKY.