Develop Reference

How to run a Service always in background (Non-Stop) - Android

I have created a Service in my android application which starts running on BOOT_COMPLETE. I want to run my Service non-stop (run always), and for that I have used while(true) inside onStartCommand() method. So is this fine to use while(true) or there is any other better way to run a service always in background?
This is code of my Service:
package com.example.abc.project1;
import android.app.Service;
import android.content.Intent;
import android.os.IBinder;
import org.json.*;
import java.io.*;
import java.net.*;
import java.util.*;
public class HelloService extends Service {
private static final String TAG = "HelloService";
private boolean isRunning = false;
#Override
public IBinder onBind(Intent arg0) {
return null;
}
#Override
public void onCreate() {
super.onCreate();
isRunning = true;
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
new Thread(new Runnable() {
#Override
public void run() {
while(true) {
/*non-stop work to be done in background always*/
}
}
}).start();
return Service.START_STICKY;
}
#Override
public void onDestroy() {
isRunning = false;
}
}

I have not tried this myself but if you change receiver to service it should work.

AsyncTask not getting excused after app is terminated?

I want perform some check continuously. I have defined AsyncTask as
follows,
new AsyncTask<String, Void, String>() {
#Override
protected void onPreExecute() {
Log.d(TAG, "onPreExecute()");
}
#Override
protected String doInBackground(String... params) {
sendData(array);
return null;
}
#Override
protected void onPostExecute(String res) { }
}.execute(userResponse);
But when I terminate the application then thread stops execution.

Service class demo :-
package com.example.My Application;
import android.app.Service;
import android.content.Intent;
import android.os.IBinder;
import android.widget.Toast;
public class MyService extends Service {
#Override
public IBinder onBind(Intent arg0) {
return null;
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
// Let it continue running until it is stopped.
Toast.makeText(this, "Service Started", Toast.LENGTH_LONG).show();
return START_STICKY;
}
#Override
public void onDestroy() {
super.onDestroy();
Toast.makeText(this, "Service Destroyed", Toast.LENGTH_LONG).show();
}
}
Activity :-
package com.example.My Application;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.content.Intent;
import android.view.View;
public class MainActivity extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
// Method to start the service
public void startService(View view) {
startService(new Intent(getBaseContext(), MyService.class));
}
// Method to stop the service
public void stopService(View view) {
stopService(new Intent(getBaseContext(), MyService.class));
}
}
Manifest :-
Add <service android:name=".MyService" />

Android listen to Lock screen displayed

I want to do a method when lock screen displayed (not when unlocked or screen on, just when lock screen displayed).
i try with broadcast and services but they don't work after killing app.
Also In eclips LogCat i see a log like /WindowManager(473): Lock screen displayed! that genymotion produce .
maybe can be done with windowmanager..

Try something like the following:
KeyguardManager myKM = (KeyguardManager)
context.getSystemService(Context.KEYGUARD_SERVICE);
if( myKM.inKeyguardRestrictedInputMode()) {
// it is locked
}
else {
// it is not locked
}
This should allow you to determine the locked status of the device.

I found it.
using service and set it START_STICKY.
after killing service the service restart again.
it is my code :
android manifest :
<application
....
<service android:name=".UpdateService" />
</application>
service class :
import android.app.Service;
import android.content.BroadcastReceiver;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.IBinder;
import android.util.Log;
import android.widget.Toast;
public class UpdateService extends Service {
BroadcastReceiver mReceiver;
#Override
public void onCreate() {
super.onCreate();
// register receiver that handles screen on and screen off logic
IntentFilter filter = new IntentFilter(Intent.ACTION_SCREEN_ON);
filter.addAction(Intent.ACTION_SCREEN_OFF);
mReceiver = new MyReceiver();
registerReceiver(mReceiver, filter);
}
#Override
public void onDestroy() {
unregisterReceiver(mReceiver);
Log.i("onDestroy Reciever", "Called");
super.onDestroy();
}
#Override
public void onStart(Intent intent, int startId) {
boolean screenOn = intent.getBooleanExtra("screen_state", false);
if ( !screenOn) {
Log.i("screenON", "Called");
Toast.makeText(getApplicationContext(), "Awake", Toast.LENGTH_LONG)
.show();
} else {
Log.i("screenOFF", "Called");
Toast.makeText(getApplicationContext(), "Sleep",
Toast.LENGTH_LONG)
.show();
}
}
#Override
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
return null;
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
return Service.START_STICKY;
}
}
receiver class :
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.util.Log;
public class MyReceiver extends BroadcastReceiver {
private boolean screenOff;
#Override
public void onReceive(Context context, Intent intent) {
if (intent.getAction().equals(Intent.ACTION_SCREEN_OFF)) {
screenOff = true;
Log.i("screenLog", "screen off");
} else if (intent.getAction().equals(Intent.ACTION_SCREEN_ON)) {
screenOff = false;
Log.i("screenLog", "screen on");
}
}
}
in StartupActivity :
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Context context = getApplicationContext();
Intent service = new Intent(context, UpdateService.class);
context.startService(service);
}

Keep a service running even if app is closed

I am implementing Service for receiving push notifications in Android device. The notifications are successfully received when app is in foreground. When app is closed and its instance is cleared from task manager, notifications are not received.
I want to keep the service running at all the times and it should not stop even if the app is cleared from the task manager.
I start the service from my activity in a button click. When i click the button my service starts and it gives me Toast notification every one minute but if I press the back button then also my service is running but , as soon as i clear my app from the recent activity list which is shown on long press of home button my service is stoped and if again i start my app and check the status of the service but its not running.
I want my service to run even if my app is closed.
This is my activity class
package com.example.hello;
import java.util.ArrayList;
import android.app.Activity;
import android.app.ActivityManager;
import android.app.ActivityManager.RunningServiceInfo;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ListView;
public class MainActivity extends Activity {
Button btnSer;
int Pointer=0;
ListView lv;
ArrayList<String> alist=new ArrayList<String>();
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btnSer=(Button) findViewById(R.id.btnstart);
btnSer.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
//start the service when the button is clicked
Log.e("","status of service : "+isMyServiceRunning(MyService.class));
//if(!isMyServiceRunning(MyService.class))
startService(new Intent(getApplicationContext(), MyService.class));
}
});
}
//check if the service is running
private boolean isMyServiceRunning(Class<?> serviceClass) {
ActivityManager manager = (ActivityManager) getSystemService(Context.ACTIVITY_SERVICE);
for (RunningServiceInfo service : manager.getRunningServices(Integer.MAX_VALUE)) {
if (serviceClass.getName().equals(service.service.getClassName())) {
return true;
}
}
return false;
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
}
This is my Service class.
package com.example.hello;
import java.util.Calendar;
import android.app.Service;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Handler;
import android.os.IBinder;
import android.util.Log;
import android.widget.Toast;
public class MyService extends Service{
private Handler handlerList = new Handler();
#Override
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
return null;
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
//TODO do something useful
Toast.makeText(getApplicationContext(), "On start command called", Toast.LENGTH_LONG).show();
return Service.START_STICKY;
}
public void updateLists(){
handlerList.postDelayed(mUpdateListTask, 1000*60);
}
private Runnable mUpdateListTask = new Runnable() {
public void run() { //will make a toast notification every 1 minute.
Calendar cal = Calendar.getInstance();
Log.e("","Thread executed at "+cal.get(Calendar.HOUR_OF_DAY)+":"+cal.get(Calendar.MINUTE)+":"+cal.get(Calendar.SECOND)+":");
Toast.makeText(getApplicationContext(), "Thread executed at "+cal.get(Calendar.HOUR_OF_DAY)+":"+cal.get(Calendar.MINUTE)+":"+cal.get(Calendar.SECOND)+":", Toast.LENGTH_LONG).show();
handlerList.postDelayed(this, 1000*60);
}};
#Override
public void onCreate() {
updateLists();
Toast.makeText(this, "Congrats! MyService Created", Toast.LENGTH_LONG).show();
Log.d("", "onCreate in service");
}
#Override
public void onStart(Intent intent, int startId) {
Toast.makeText(this, "My Service Started", Toast.LENGTH_LONG).show();
Log.d("", "onStart in service");
}
#Override
public void onDestroy() {
Toast.makeText(this, "MyService Stopped", Toast.LENGTH_LONG).show();
Log.d("", "onDestroy in service");
}
}
also added the permission in manifest file
<uses-permission android:name="android.permission.WAKE_LOCK" />

Start it as foreground service in the activity use startforeground(intent name) and return it as sticky in the service onstartCommand() method.

Creating an android service

I'm trying to create a service which will start by the user request in the application.
After the user will choose an update interval, the service will run in the operation system background, and will send a non-relevant message.
I've tried to write the service according to the example for Service class API.
For some reason, I figured in debug (when running doBindService() method) that mUpdateBoundService is getting null.
My second question is whether I can use "Toast" inform message outside an application ? (As kind of a desktop notification).
Can anyone help ? Here is my short code:
UpdateService.java
package android.update;
import java.util.Timer;
import java.util.TimerTask;
import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.app.Service;
import android.content.Intent;
import android.os.Binder;
import android.os.IBinder;
import android.widget.Toast;
public class UpdateService extends Service {
private NotificationManager mNM;
private final IBinder mBinder = new UpdateBinder();
private int updateInterval;
public class UpdateBinder extends Binder {
UpdateService getService() {
return UpdateService.this;
}
}
public void onCreate() {
mNM = (NotificationManager)getSystemService(NOTIFICATION_SERVICE);
Timer timer = new Timer();
timer.schedule(new UpdateTimeTask(), 100, updateInterval);
}
public int onStartCommand(Intent intent, int flags, int startId) {
return START_STICKY;
}
class UpdateTimeTask extends TimerTask {
public void run() {
showNotification();
}
}
public void showNotification() {
Toast.makeText(this, "Hi", 10);
}
#Override
public IBinder onBind(Intent intent) {
updateInterval = intent.getExtras().getInt(getString(R.string.keyUpdateInterval));
return mBinder;
}
}
UpdateActivity.java
package android.update;
import android.app.Activity;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.ServiceConnection;
import android.os.Bundle;
import android.os.IBinder;
import android.view.View;
import android.widget.EditText;
import android.widget.Toast;
public class UpdateActivity extends Activity {
private UpdateService mUpdateBoundService;
private boolean mIsBound = false;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
}
public void onClickStartUpdateService(View view) {
switch (view.getId()) {
case R.id.btnStartUpdateService:
doBindService();
//Toast.makeText(this,"Service Started",Toast.LENGTH_LONG).show();
mUpdateBoundService.showNotification();
break;
}
}
private ServiceConnection mConnection = new ServiceConnection() {
public void onServiceConnected(ComponentName className, IBinder service) {
mUpdateBoundService = ((UpdateService.UpdateBinder)service).getService();
}
public void onServiceDisconnected(ComponentName className) {
mUpdateBoundService = null;
}
};
private void doBindService() {
Intent updateActivityIntent = new Intent(UpdateActivity.this,
UpdateService.class);
EditText txtUpdateInterval = (EditText) findViewById(R.id.txtUpdateInterval);
int interval = Integer.parseInt(txtUpdateInterval.getText().toString());
updateActivityIntent.putExtra(getString(R.string.keyUpdateInterval), interval);
bindService(updateActivityIntent, mConnection, Context.BIND_AUTO_CREATE);
mIsBound = true;
}
void doUnbindService() {
if (mIsBound) {
unbindService(mConnection);
mIsBound = false;
}
}
#Override
protected void onDestroy() {
super.onDestroy();
doUnbindService();
}
}

Your toast is not showing because you are not telling it to. Try:
public void showNotification() {
Toast.makeText(this, "Hi", 10).show();
}
For your service issue, I think that you do not properly understand how services & activities work together. A service can run independently of a service, or you can have a service whose lifecycle matches that of a given activity. From your code, it is not clear which of these models you are following. Your implementation will cause the service to wake periodically, but only while your activity is running. If the user switches to another activity, your service will no longer be woken.
If you want a service to wake periodically independently of the activity, then you need to run your timer event in the service itself. Better still use an Alarm to wake your service: Register an Alarm with AlarmManager which will fire an Intent at a future point (or regular intervals, if you prefer), and extend your service from IntentService, override onHandleIntent() and add the necessary Intent Filter to your Service entry in the manifest.