Download using DownloadManager

The class android.app.DownloadManager (Since: API Level 9) is a system service that handles long-running HTTP downloads. Clients may request that a URI be downloaded to a particular destination file. The download manager will conduct the download in the background, taking care of HTTP interactions and retrying downloads after failures or across connectivity changes and system reboots.

It's a basic code to download file from internet using DownloadManager.

package com.AndroidDownload;

import java.io.FileInputStream;
import java.io.FileNotFoundException;

import android.app.Activity;
import android.app.DownloadManager;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.net.Uri;
import android.os.Bundle;
import android.os.ParcelFileDescriptor;
import android.preference.PreferenceManager;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

public class AndroidDownloadActivity extends Activity {
 
 String Download_path = "http://goo.gl/Mfyya";
 String Download_ID = "DOWNLOAD_ID";
 
 SharedPreferences preferenceManager;
 DownloadManager downloadManager;
 
   /** Called when the activity is first created. */
   @Override
   public void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.main);
      
       preferenceManager = PreferenceManager.getDefaultSharedPreferences(this);
       downloadManager = (DownloadManager)getSystemService(DOWNLOAD_SERVICE);
      
       Button btnDownload = (Button)findViewById(R.id.download);
       btnDownload.setOnClickListener(new Button.OnClickListener(){

   @Override
   public void onClick(View arg0) {
    // TODO Auto-generated method stub
    Uri Download_Uri = Uri.parse(Download_path);
    DownloadManager.Request request = new DownloadManager.Request(Download_Uri);
    long download_id = downloadManager.enqueue(request);
    
    //Save the download id
    Editor PrefEdit = preferenceManager.edit();
    PrefEdit.putLong(Download_ID, download_id);
    PrefEdit.commit();
   }});
   }
  
 @Override
 protected void onResume() {
  // TODO Auto-generated method stub
  super.onResume();
  
  IntentFilter intentFilter = new IntentFilter(DownloadManager.ACTION_DOWNLOAD_COMPLETE);
  registerReceiver(downloadReceiver, intentFilter);
 }

 @Override
 protected void onPause() {
  // TODO Auto-generated method stub
  super.onPause();
  
  unregisterReceiver(downloadReceiver);
 }

 private BroadcastReceiver downloadReceiver = new BroadcastReceiver() {

  @Override
  public void onReceive(Context arg0, Intent arg1) {
   // TODO Auto-generated method stub
   DownloadManager.Query query = new DownloadManager.Query();
   query.setFilterById(preferenceManager.getLong(Download_ID, 0));
   Cursor cursor = downloadManager.query(query);
   
   if(cursor.moveToFirst()){
    int columnIndex = cursor.getColumnIndex(DownloadManager.COLUMN_STATUS);
    int status = cursor.getInt(columnIndex);
    int columnReason = cursor.getColumnIndex(DownloadManager.COLUMN_REASON);
    int reason = cursor.getInt(columnReason);
    
    if(status == DownloadManager.STATUS_SUCCESSFUL){
     //Retrieve the saved download id
     long downloadID = preferenceManager.getLong(Download_ID, 0);
     
     ParcelFileDescriptor file;
     try {
      file = downloadManager.openDownloadedFile(downloadID);
      Toast.makeText(AndroidDownloadActivity.this,
        "File Downloaded: " + file.toString(),
        Toast.LENGTH_LONG).show();
     } catch (FileNotFoundException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
      Toast.makeText(AndroidDownloadActivity.this,
        e.toString(),
        Toast.LENGTH_LONG).show();
     }
     
    }else if(status == DownloadManager.STATUS_FAILED){
     Toast.makeText(AndroidDownloadActivity.this,
       "FAILED!\n" + "reason of " + reason,
       Toast.LENGTH_LONG).show();
    }else if(status == DownloadManager.STATUS_PAUSED){
     Toast.makeText(AndroidDownloadActivity.this,
       "PAUSED!\n" + "reason of " + reason,
       Toast.LENGTH_LONG).show();
    }else if(status == DownloadManager.STATUS_PENDING){
     Toast.makeText(AndroidDownloadActivity.this,
       "PENDING!",
       Toast.LENGTH_LONG).show();
    }else if(status == DownloadManager.STATUS_RUNNING){
     Toast.makeText(AndroidDownloadActivity.this,
       "RUNNING!",
       Toast.LENGTH_LONG).show();
    }
   }
  }
  
 };

}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
   android:layout_width="fill_parent"
   android:layout_height="fill_parent"
   android:orientation="vertical" >

   <TextView
       android:layout_width="fill_parent"
       android:layout_height="wrap_content"
       android:text="@string/hello" />
   <Button
       android:id="@+id/download"
       android:layout_width="fill_parent"
       android:layout_height="wrap_content"
       android:text="Start Download" />

</LinearLayout>

remark: "android.permission.INTERNET" is needed in AndroidManifest.xml.

next: Remove from DownloadManager

Download using DownloadManager

The class android.app.DownloadManager (Since: API Level 9) is a system service that handles long-running HTTP downloads. Clients may request that a URI be downloaded to a particular destination file. The download manager will conduct the download in the background, taking care of HTTP interactions and retrying downloads after failures or across connectivity changes and system reboots.

It's a basic code to download file from internet using DownloadManager.

package com.AndroidDownload;

import java.io.FileInputStream;
import java.io.FileNotFoundException;

import android.app.Activity;
import android.app.DownloadManager;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.net.Uri;
import android.os.Bundle;
import android.os.ParcelFileDescriptor;
import android.preference.PreferenceManager;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

public class AndroidDownloadActivity extends Activity {
 
 String Download_path = "http://goo.gl/Mfyya";
 String Download_ID = "DOWNLOAD_ID";
 
 SharedPreferences preferenceManager;
 DownloadManager downloadManager;
 
   /** Called when the activity is first created. */
   @Override
   public void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.main);
      
       preferenceManager = PreferenceManager.getDefaultSharedPreferences(this);
       downloadManager = (DownloadManager)getSystemService(DOWNLOAD_SERVICE);
      
       Button btnDownload = (Button)findViewById(R.id.download);
       btnDownload.setOnClickListener(new Button.OnClickListener(){

   @Override
   public void onClick(View arg0) {
    // TODO Auto-generated method stub
    Uri Download_Uri = Uri.parse(Download_path);
    DownloadManager.Request request = new DownloadManager.Request(Download_Uri);
    long download_id = downloadManager.enqueue(request);
    
    //Save the download id
    Editor PrefEdit = preferenceManager.edit();
    PrefEdit.putLong(Download_ID, download_id);
    PrefEdit.commit();
   }});
   }
  
 @Override
 protected void onResume() {
  // TODO Auto-generated method stub
  super.onResume();
  
  IntentFilter intentFilter = new IntentFilter(DownloadManager.ACTION_DOWNLOAD_COMPLETE);
  registerReceiver(downloadReceiver, intentFilter);
 }

 @Override
 protected void onPause() {
  // TODO Auto-generated method stub
  super.onPause();
  
  unregisterReceiver(downloadReceiver);
 }

 private BroadcastReceiver downloadReceiver = new BroadcastReceiver() {

  @Override
  public void onReceive(Context arg0, Intent arg1) {
   // TODO Auto-generated method stub
   DownloadManager.Query query = new DownloadManager.Query();
   query.setFilterById(preferenceManager.getLong(Download_ID, 0));
   Cursor cursor = downloadManager.query(query);
   
   if(cursor.moveToFirst()){
    int columnIndex = cursor.getColumnIndex(DownloadManager.COLUMN_STATUS);
    int status = cursor.getInt(columnIndex);
    int columnReason = cursor.getColumnIndex(DownloadManager.COLUMN_REASON);
    int reason = cursor.getInt(columnReason);
    
    if(status == DownloadManager.STATUS_SUCCESSFUL){
     //Retrieve the saved download id
     long downloadID = preferenceManager.getLong(Download_ID, 0);
     
     ParcelFileDescriptor file;
     try {
      file = downloadManager.openDownloadedFile(downloadID);
      Toast.makeText(AndroidDownloadActivity.this,
        "File Downloaded: " + file.toString(),
        Toast.LENGTH_LONG).show();
     } catch (FileNotFoundException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
      Toast.makeText(AndroidDownloadActivity.this,
        e.toString(),
        Toast.LENGTH_LONG).show();
     }
     
    }else if(status == DownloadManager.STATUS_FAILED){
     Toast.makeText(AndroidDownloadActivity.this,
       "FAILED!\n" + "reason of " + reason,
       Toast.LENGTH_LONG).show();
    }else if(status == DownloadManager.STATUS_PAUSED){
     Toast.makeText(AndroidDownloadActivity.this,
       "PAUSED!\n" + "reason of " + reason,
       Toast.LENGTH_LONG).show();
    }else if(status == DownloadManager.STATUS_PENDING){
     Toast.makeText(AndroidDownloadActivity.this,
       "PENDING!",
       Toast.LENGTH_LONG).show();
    }else if(status == DownloadManager.STATUS_RUNNING){
     Toast.makeText(AndroidDownloadActivity.this,
       "RUNNING!",
       Toast.LENGTH_LONG).show();
    }
   }
  }
  
 };

}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
   android:layout_width="fill_parent"
   android:layout_height="fill_parent"
   android:orientation="vertical" >

   <TextView
       android:layout_width="fill_parent"
       android:layout_height="wrap_content"
       android:text="@string/hello" />
   <Button
       android:id="@+id/download"
       android:layout_width="fill_parent"
       android:layout_height="wrap_content"
       android:text="Start Download" />

</LinearLayout>

remark: "android.permission.INTERNET" is needed in AndroidManifest.xml.

Interactive between Activity and Service

Modify from last post Pass data from Activity to Service via Intent in startService(); a BroadcastReceiver is added in MyService, such that our main activity (AndroidServiceTestActivity) can send data (CMD) to service via another intent(MY_ACTION_FROMACTIVITY).



MyService.java

package com.AndroidServiceTest;

import android.app.Service;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.IBinder;
import android.widget.Toast;

public class MyService extends Service {
 
 MyServiceReceiver myServiceReceiver;

 final static String MY_ACTION = "MY_ACTION";
 final static String MY_ACTION_FROMACTIVITY = "MY_ACTION_FROMACTIVITY";
 
 public static final String CMD = "CMD";
 public static final int CMD_STOP = 1;
 boolean running;
 
 String initData;

 @Override
 public void onCreate() {
  // TODO Auto-generated method stub
  myServiceReceiver = new MyServiceReceiver();
  super.onCreate();
 }

 @Override
 public IBinder onBind(Intent arg0) {
  // TODO Auto-generated method stub
  return null;
 }

 @Override
 public int onStartCommand(Intent intent, int flags, int startId) {
  // TODO Auto-generated method stub
  
  IntentFilter intentFilter = new IntentFilter();
  intentFilter.addAction(MY_ACTION_FROMACTIVITY);
  registerReceiver(myServiceReceiver, intentFilter);
  running = true;
  
  initData = intent.getStringExtra("INIT_DATA");
  
  MyThread myThread = new MyThread();
  myThread.start();
  
  return super.onStartCommand(intent, flags, startId);
 }
 
 @Override
 public void onDestroy() {
  // TODO Auto-generated method stub
  this.unregisterReceiver(myServiceReceiver);
  super.onDestroy();
 }

 public class MyThread extends Thread{

  @Override
  public void run() {
   // TODO Auto-generated method stub
   int i = 0;
   while(running){
    try {
     Thread.sleep(5000);
     Intent intent = new Intent();
        intent.setAction(MY_ACTION);
       
        intent.putExtra("DATAPASSED", i);
        intent.putExtra("DATA_BACK", initData);
       
        sendBroadcast(intent);
       
        i++;
    } catch (InterruptedException e) {
     // TODO Auto-generated catch block
     e.printStackTrace();
    }
   }
   stopSelf();
  }

 }
 
 public class MyServiceReceiver extends BroadcastReceiver {

  @Override
  public void onReceive(Context arg0, Intent arg1) {
   // TODO Auto-generated method stub
   int hostCmd = arg1.getIntExtra(CMD, 0);
   if(hostCmd == CMD_STOP){
    running = false;
       stopSelf();
      
       Toast.makeText(MyService.this,
         "Service stopped by main Activity!",
         Toast.LENGTH_LONG).show();
   }
  }

 }

}

Modify main activity (AndroidServiceTestActivity.java) to send command to stop our service, by pressing of the Stop button.

package com.AndroidServiceTest;

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

public class AndroidServiceTestActivity extends Activity {
 
 MyReceiver myReceiver;
 
 Button btnStop;
 
   /** Called when the activity is first created. */
   @Override
   public void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.main);
       btnStop = (Button)findViewById(R.id.stop);
       btnStop.setOnClickListener(new Button.OnClickListener(){

   @Override
   public void onClick(View arg0) {
    // TODO Auto-generated method stub
    Intent intent = new Intent();
    intent.setAction(MyService.MY_ACTION_FROMACTIVITY);
    intent.putExtra(MyService.CMD, MyService.CMD_STOP);
    sendBroadcast(intent);
   }});

   }

 @Override
 protected void onStart() {
  // TODO Auto-generated method stub
  
       //Register BroadcastReceiver
       //to receive event from our service
       myReceiver = new MyReceiver();
       IntentFilter intentFilter = new IntentFilter();
       intentFilter.addAction(MyService.MY_ACTION);
       registerReceiver(myReceiver, intentFilter);
      
       //Start our own service
       Intent intent = new Intent(AndroidServiceTestActivity.this,
         com.AndroidServiceTest.MyService.class);
       intent.putExtra("INIT_DATA", "Data passed from Activity to Service in startService");
       startService(intent);
  
  super.onStart();
 }

 @Override
 protected void onStop() {
  // TODO Auto-generated method stub
  unregisterReceiver(myReceiver);
  super.onStop();
 }
 
 private class MyReceiver extends BroadcastReceiver{

  @Override
  public void onReceive(Context arg0, Intent arg1) {
   // TODO Auto-generated method stub
   
   int datapassed = arg1.getIntExtra("DATAPASSED", 0);
   String orgData = arg1.getStringExtra("DATA_BACK");
   
   Toast.makeText(AndroidServiceTestActivity.this,
     "Triggered by Service!\n"
     + "Data passed: " + String.valueOf(datapassed) + "\n"
     + "original Data: " + orgData,
     Toast.LENGTH_LONG).show();
   
  }
  
 }
}

Modify layout to add the Stop button.

<?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/stop"
   android:layout_width="fill_parent"
   android:layout_height="wrap_content"
   android:text="Stop"
   />
</LinearLayout>

Pass data from Activity to Service via Intent in startService()

In this example, modify from last post Pass data from Service to Activity, Extra is pass from Activity to Service in startService(). It will be retrieved in onStartCommand() of Service.



AndroidServiceTestActivity.java

package com.AndroidServiceTest;

import android.app.Activity;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.widget.Toast;

public class AndroidServiceTestActivity extends Activity {

MyReceiver myReceiver;

  /** Called when the activity is first created. */
  @Override
  public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.main);

  }

@Override
protected void onStart() {
 // TODO Auto-generated method stub

      //Register BroadcastReceiver
      //to receive event from our service
      myReceiver = new MyReceiver();
      IntentFilter intentFilter = new IntentFilter();
      intentFilter.addAction(MyService.MY_ACTION);
      registerReceiver(myReceiver, intentFilter);
    
      //Start our own service
      Intent intent = new Intent(AndroidServiceTestActivity.this,
        com.AndroidServiceTest.MyService.class);
      intent.putExtra("INIT_DATA", "Data passed from Activity to Service in startService");
      startService(intent);

 super.onStart();
}

@Override
protected void onStop() {
 // TODO Auto-generated method stub
 unregisterReceiver(myReceiver);
 super.onStop();
}

private class MyReceiver extends BroadcastReceiver{

 @Override
 public void onReceive(Context arg0, Intent arg1) {
  // TODO Auto-generated method stub
 
  int datapassed = arg1.getIntExtra("DATAPASSED", 0);
  String orgData = arg1.getStringExtra("DATA_BACK");
 
  Toast.makeText(AndroidServiceTestActivity.this,
    "Triggered by Service!\n"
    + "Data passed: " + String.valueOf(datapassed) + "\n"
    + "original Data: " + orgData,
    Toast.LENGTH_LONG).show();
 
 }

}
}

package com.AndroidServiceTest;

import android.app.Service;
import android.content.Intent;
import android.os.IBinder;

public class MyService extends Service {

final static String MY_ACTION = "MY_ACTION";
String initData;

@Override
public IBinder onBind(Intent arg0) {
 // TODO Auto-generated method stub
 return null;
}

@Override
public int onStartCommand(Intent intent, int flags, int startId) {
 // TODO Auto-generated method stub

 initData = intent.getStringExtra("INIT_DATA");

 MyThread myThread = new MyThread();
 myThread.start();

 return super.onStartCommand(intent, flags, startId);
}

public class MyThread extends Thread{

 @Override
 public void run() {
  // TODO Auto-generated method stub
  for(int i=0; i<10; i++){
   try {
    Thread.sleep(5000);
    Intent intent = new Intent();
       intent.setAction(MY_ACTION);
     
       intent.putExtra("DATAPASSED", i);
       intent.putExtra("DATA_BACK", initData);
     
       sendBroadcast(intent);
   } catch (InterruptedException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
   }
  }
  stopSelf();
 }

}

}

Note: Modify AndroidManifest.xml to add service ".MyService", refer to the post Create our own Service and BroadcastReceiver.

Next post:
- Interactive between Activity and Service

Pass data from Service to Activity

Refer to the last post Create our own Service and BroadcastReceiver, data can be passed from Service using intent.putExtra(); on the other hand, the data passed can be retrieved using getIntExtra() in BroadcastReceiver.



Modify from the last post Create our own Service and BroadcastReceiver.
AndroidServiceTestActivity.java

package com.AndroidServiceTest;

import android.app.Activity;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.widget.Toast;

public class AndroidServiceTestActivity extends Activity {

MyReceiver myReceiver;

  /** Called when the activity is first created. */
  @Override
  public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.main);

  }

@Override
protected void onStart() {
 // TODO Auto-generated method stub

      //Register BroadcastReceiver
      //to receive event from our service
      myReceiver = new MyReceiver();
      IntentFilter intentFilter = new IntentFilter();
      intentFilter.addAction(MyService.MY_ACTION);
      registerReceiver(myReceiver, intentFilter);
    
      //Start our own service
      Intent intent = new Intent(AndroidServiceTestActivity.this,
        com.AndroidServiceTest.MyService.class);
      startService(intent);

 super.onStart();
}

@Override
protected void onStop() {
 // TODO Auto-generated method stub
 unregisterReceiver(myReceiver);
 super.onStop();
}

private class MyReceiver extends BroadcastReceiver{

 @Override
 public void onReceive(Context arg0, Intent arg1) {
  // TODO Auto-generated method stub
 
  int datapassed = arg1.getIntExtra("DATAPASSED", 0);
 
  Toast.makeText(AndroidServiceTestActivity.this,
    "Triggered by Service!\n"
    + "Data passed: " + String.valueOf(datapassed),
    Toast.LENGTH_LONG).show();
 
 }

}
}

MyService.java

package com.AndroidServiceTest;

import android.app.Service;
import android.content.Intent;
import android.os.IBinder;

public class MyService extends Service {

final static String MY_ACTION = "MY_ACTION";

@Override
public IBinder onBind(Intent arg0) {
 // TODO Auto-generated method stub
 return null;
}

@Override
public int onStartCommand(Intent intent, int flags, int startId) {
 // TODO Auto-generated method stub

 MyThread myThread = new MyThread();
 myThread.start();

 return super.onStartCommand(intent, flags, startId);
}

public class MyThread extends Thread{

 @Override
 public void run() {
  // TODO Auto-generated method stub
  for(int i=0; i<10; i++){
   try {
    Thread.sleep(5000);
    Intent intent = new Intent();
       intent.setAction(MY_ACTION);
     
       intent.putExtra("DATAPASSED", i);
     
       sendBroadcast(intent);
   } catch (InterruptedException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
   }
  }
  stopSelf();
 }

}

}

Note: Modify AndroidManifest.xml to add service ".MyService", refer to the post Create our own Service and BroadcastReceiver.

Next:
- Pass data from Activity to Service via Intent in startService()

Create our own Service and BroadcastReceiver

In this onStart() of the main activity(AndroidServiceTestActivity.java), we instance and register our own BroadcastReceiver(myReceiver), and also start our service(MyService.java). In MyService.java, It will send 10 actions with MY_ACTION. It will trigger the myReceiver in AndroidServiceTestActivity.java.



Main activity AndroidServiceTestActivity.java

package com.AndroidServiceTest;

import android.app.Activity;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.widget.Toast;

public class AndroidServiceTestActivity extends Activity {

MyReceiver myReceiver;

   /** Called when the activity is first created. */
   @Override
   public void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.main);

   }

@Override
protected void onStart() {
 // TODO Auto-generated method stub

       //Register BroadcastReceiver
       //to receive event from our service
       myReceiver = new MyReceiver();
       IntentFilter intentFilter = new IntentFilter();
       intentFilter.addAction(MyService.MY_ACTION);
       registerReceiver(myReceiver, intentFilter);
      
       //Start our own service
       Intent intent = new Intent(AndroidServiceTestActivity.this,
         com.AndroidServiceTest.MyService.class);
       startService(intent);

 super.onStart();
}

@Override
protected void onStop() {
 // TODO Auto-generated method stub
 unregisterReceiver(myReceiver);
 super.onStop();
}

private class MyReceiver extends BroadcastReceiver{

 @Override
 public void onReceive(Context arg0, Intent arg1) {
  // TODO Auto-generated method stub
  Toast.makeText(AndroidServiceTestActivity.this,
    "Triggered by Service!",
    Toast.LENGTH_LONG).show();
 
 }

}
}

MyService.java

package com.AndroidServiceTest;

import android.app.Service;
import android.content.Intent;
import android.os.IBinder;

public class MyService extends Service {

final static String MY_ACTION = "MY_ACTION";

@Override
public IBinder onBind(Intent arg0) {
 // TODO Auto-generated method stub
 return null;
}

@Override
public int onStartCommand(Intent intent, int flags, int startId) {
 // TODO Auto-generated method stub

 MyThread myThread = new MyThread();
 myThread.start();

 return super.onStartCommand(intent, flags, startId);
}

public class MyThread extends Thread{

 @Override
 public void run() {
  // TODO Auto-generated method stub
  for(int i=0; i<10; i++){
   try {
    Thread.sleep(5000);
    Intent intent = new Intent();
       intent.setAction(MY_ACTION);
       sendBroadcast(intent);
   } catch (InterruptedException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
   }
  }
  stopSelf();
 }

}

}

Modify AndroidManifest.xml to add service ".MyService"

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
     package="com.AndroidServiceTest"
     android:versionCode="1"
     android:versionName="1.0">
   <uses-sdk android:minSdkVersion="7" />

   <application android:icon="@drawable/icon" android:label="@string/app_name">
       <activity android:name=".AndroidServiceTestActivity"
                 android:label="@string/app_name">
           <intent-filter>
               <action android:name="android.intent.action.MAIN" />
               <category android:name="android.intent.category.LAUNCHER" />
           </intent-filter>
       </activity>
 <service android:name=".MyService"/>
   </application>
</manifest>

next:
- Pass data from Service to Activity