Develop Reference

Want to make a persistent service like Whatsapp/Truecaller

Description of Truecaller/Whatsapp service
**Note: Here force close means killing the app by pressing and holding back button not just stopping the service from service manager/app manager (see Kill app back button).
After killing the truecaller app when I make a call it restarts automatically, same for whatsapp also, After killing it when a message is received it still shows the notification and restarts the service. These services also restarts after a few delay
What I have done so far to achieve this
I want to make a service like this so called my backgroundservice from onDestroy() of my backgroundservice class. Code for this: ServiceDemo 0.1
public class BackgroundService extends Service {
#Nullable
#Override
public IBinder onBind(Intent intent) {
return null;
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
Toast.makeText(BackgroundService.this, "Service Started...", Toast.LENGTH_SHORT).show();
return START_STICKY;
}
#Override
public void onDestroy() {
Intent intentService = new Intent(this,BackgroundService.class);
startService(intentService);
Toast.makeText(BackgroundService.this, "Service Will Be Restarted...", Toast.LENGTH_SHORT).show();
}
}
The service is restarting if I stop it from my service manager. But if I force close/kill it , it's gone.
After this I implemented Broadcast receiver which doesn't make any difference. Code for this: ServiceDemo 0.2
BackgroundService.java
public class BackgroundService extends Service {
#Nullable
#Override
public IBinder onBind(Intent intent) {
return null;
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
Toast.makeText(BackgroundService.this, "Service Started...", Toast.LENGTH_SHORT).show();
return START_STICKY;
}
#Override
public void onDestroy() {
Toast.makeText(BackgroundService.this, "Service Will Be Restarted...", Toast.LENGTH_SHORT).show();
sendBroadcast(new Intent("RestartMe"));
}
}
RestartBackgroundService.java
public class RestartBackgroundService extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
// I have also used AlarmManager , but it doesn't make any difference for me
// AlarmManager am = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
// PendingIntent pi = PendingIntent.getService(context, 0, new Intent(context, BackgroundService.class), PendingIntent.FLAG_UPDATE_CURRENT);
// int interval = 5000;
// am.setInexactRepeating(AlarmManager.RTC_WAKEUP, System.currentTimeMillis() + interval, interval, pi);
context.startService(new Intent(context.getApplicationContext(),BackgroundService.class));
}
}
As whatsapp is using gcm so I thought if I implement that it would help.
Then I implemented firebase cloud messaging (fcm) to receive push notification and I removed the code to restart background service from onDestroy().
Now if I stops the service from service manager it remains stopped then I sends a notification from my firebase console it receives the notification as google's gcm service is running. If I click the notification it restarts my service again.
But if I force close/kill my app no notifications are received though gcm service is running. Code for this: (I posted a link to make the description a bit short)
ServiceDemo 0.3
What I want
I want my service to be persistent like whatsapp/truecaller even if I force close it. They keep on starting after a few delays. And I want to achieve it without using third parties like fcm.
If someone can give any hints/solution about how to start my service when a particular system service/app (like dialer) starts that would be a great help.

run service even if the application is closed (killed)

I want that this service run even if the application is closed (kiiled) or even if the user dont start the app.
i want the service start after the application is installed and from this point, the service should run always.
public class notifications extends Service {
#Override
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
return null;
}
#Override
public void onCreate() {
}
#Override
public void onStart(Intent intent, int startId) {
final Handler handler = new Handler();
final Runnable runb = new Runnable()
{
public void run()
{
Toast.makeText(getApplicationContext(), " Service Started", Toast.LENGTH_LONG).show();
handler.postDelayed(this, 10000);
}
};
handler.postDelayed(runb, 0);
}
#Override
public void onDestroy() {
}
}*/
public class notifications extends IntentService
{
private Timer mBackGroundTimer;
public notifications()
{
super("myservice");
this.mBackGroundTimer=new Timer();
}
#Override
protected void onHandleIntent(Intent intent)
{
// TODO Auto-generated method stub
mBackGroundTimer.schedule(new TimerTask()
{
public void run()
{
try
{
Notification("This is message from Dipak Keshariya (Android Application Developer)", "This is Android Notification Message");
}
catch (Exception e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}
}
},1000, 2000);
} // END onHandleIntent()
private void mStopTimer()
{
//Call this whenever you need to stop the service
mBackGroundTimer.cancel();
}
private void Notification(String notificationTitle, String notificationMessage) {
NotificationManager notificationManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
android.app.Notification notification = new android.app.Notification(R.drawable.ic_launcher, "A New Message from Dipak Keshariya (Android Developer)!",
System.currentTimeMillis());
Intent notificationIntent = new Intent(this, MainActivity.class);
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, notificationIntent, 0);
notification.setLatestEventInfo(getApplicationContext(), notificationTitle, notificationMessage, pendingIntent);
notificationManager.notify(10001, notification);
}
}
how i can do that?

Looking at your code, it appears you want your service to periodically give notifications.
As far as having it run continuously goes, keep in mind that by design, the Android system may terminate your service process at any time. You can influence this a bit, but you cannot prevent the system from killing your service.
So for your periodical actions, it would be best to use AlarmManager with a recurring alarm. Your service would then basically be one-shot, i.e. perform the action once and then exit.
For some code, look here for example:
Android: Alarm Manager

You need to implement the OnStartCommand method of the Service class and in it, return Service.START_STICKY. That will do the trick. If you kill the application, the service will continue to run in the background. However, if you restart your phone, I think you need to implement something else in your app, as well, a boot service or something like that.

As you requirement is to run the service in the background. you are on the right track to use the service because this is meant for background running purpose only.
from the activitiy you can start the service by
startService(new Intent(activityName.this, serviceName.class));
or if your application is not having any activity then you can make the service as default and main launcher of the application by putting
<service android:name="name of the service" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</service>

I think answer to this question is this : https://developer.android.com/training/sync-adapters/creating-sync-adapter.html
Sync Adapters introduced in Google I/O 2013.

Service stops when deploying android app (disapears from settings>>application>>RunningServices)

This is my situation: I have a service running and every time I deploy my app the service disappears from settings>>application>>runningService (therefore, the service is not running) how can I set it so that the service does not disappears?
I have tried to startForeground but it did not worked.
AndroidManifest:
<service
android:name=".service.PhoneCallInOutService"
android:enabled="true"
android:exported="false" >
</service>
This is how I start the service in my Activity:
chkCallsRecord.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
boolean isChecked = chkCallsRecord.isChecked();
updateBackgroundTasks(isChecked);
}
});
The method actually starting the service:
private void updateBackgroundTasks(boolean start) {
Intent serviceIntent = new Intent(getApplicationContext(),PhoneCallInOutService.class);
if (start) {
getApplicationContext().startService(serviceIntent);
} else {
getApplicationContext().stopService(serviceIntent);
}
}
And here is the service:
public class PhoneCallInOutService extends Service {
private TelephonyManager telephonyMgr;
private PhoneCallStateListener pcsListener;
private OutgoingCallReceiver ocReceiver;
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
super.onStartCommand(intent, flags, startId);
// Listener
pcsListener = new PhoneCallStateListener(getApplicationContext(),appDto);
telephonyMgr = (TelephonyManager)getApplicationContext().getSystemService(Context.TELEPHONY_SERVICE);
telephonyMgr.listen(pcsListener, PhoneStateListener.LISTEN_CALL_STATE);
// Receiver
ocReceiver = new OutgoingCallReceiver(getApplication());
IntentFilter intentF = new IntentFilter(Intent.ACTION_NEW_OUTGOING_CALL);
getApplicationContext().registerReceiver(ocReceiver, intentF);
return START_STICKY;
}
#Override
public void onDestroy() {
super.onDestroy();
// Listener
telephonyMgr.listen(pcsListener, PhoneStateListener.LISTEN_NONE);
// Receiver
getApplicationContext().unregisterReceiver(ocReceiver);
}
#Override
public IBinder onBind(Intent arg0) {
return null;
}
}
Thank you very much in advance.

If by deploy you mean you try to launch new build of your app, then this is actually normal and expected behaviour. By deploying new build you replace old code (incl. service code) therefore it have to be killed first to avoid any crashes and other oddities. So your old iteration of app is completely killed. Then new app is installed and most often auto-launched. Your data create by the app usually stay, but it's also normal.
EDIT
For security reasons you are not allowed to re-launch itself after being updated. User has to to this. As for "he/she may assume the service is still there running, which is not true", use notification of type "On Going" to indicate running service

Android - Periodic Background Service - Advice

I am working on an app that will relay information about its location to a remote server. I am intending to do it by doing a simple HTTP post to the web-server and all is simple and fine.
But according to the spec, the app needs to execute itself from time to time, lets say once in every 30 mins. Be independent of the interface, meaning which it needs to run even if the app is closed.
I looked around and found out that Android Services is what needs to be used. What could I use to implement such a system. Will the service (or other mechanism) restart when the phone restarts?
Thanks in advance.

Create a Service to send your information to your server. Presumably, you've got that under control.
Your Service should be started by an alarm triggered by the AlarmManager, where you can specify an interval. Unless you have to report your data exactly every 30 minutes, you probably want the inexact alarm so you can save some battery life.
Finally, you can register your app to get the bootup broadcast by setting up a BroadcastReceiver like so:
public class BootReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
if (intent.getAction().equals(Intent.ACTION_BOOT_COMPLETED)) {
// Register your reporting alarms here.
}
}
}
You'll need to add the following permission to your AndroidManifest.xml for that to work. Don't forget to register your alarms when you run the app normally, or they'll only be registered when the device boots up.
<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>

Here is a semi-different way to keep the service going forever. There is ways to kill it in code if you'd wish
Background Service:
package com.ex.ample;
import android.app.Service;
import android.content.*;
import android.os.*;
import android.widget.Toast;
public class BackgroundService extends Service {
public Context context = this;
public Handler handler = null;
public static Runnable runnable = null;
#Override
public IBinder onBind(Intent intent) {
return null;
}
#Override
public void onCreate() {
Toast.makeText(this, "Service created!", Toast.LENGTH_LONG).show();
handler = new Handler();
runnable = new Runnable() {
public void run() {
Toast.makeText(context, "Service is still running", Toast.LENGTH_LONG).show();
handler.postDelayed(runnable, 10000);
}
};
handler.postDelayed(runnable, 15000);
}
#Override
public void onDestroy() {
/* IF YOU WANT THIS SERVICE KILLED WITH THE APP THEN UNCOMMENT THE FOLLOWING LINE */
//handler.removeCallbacks(runnable);
Toast.makeText(this, "Service stopped", Toast.LENGTH_LONG).show();
}
#Override
public void onStart(Intent intent, int startid) {
Toast.makeText(this, "Service started by user.", Toast.LENGTH_LONG).show();
}
}
Here is how you start it from your main activity or wherever you wish:
startService(new Intent(this, BackgroundService.class));
onDestroy() will get called when the application gets closed or killed but the runnable just starts it right back up.
I hope this helps someone out.
The reason why some people do this is because of corporate applications where in some instances the users/employees must not be able to stop certain things :)
http://i.imgur.com/1vCnYJW.png
EDIT
Since Android O (8.0) you have to use JobManager for scheduled tasks. There is a library called Android-Job by Evernote which will make periodic background work a breeze on all Android versions. I have also made a Xamarin Binding of this library.
Then all you need to do is the following:
In your application class:
public class MyApp extends Application {
#Override
public void onCreate() {
super.onCreate();
JobManager.create(this).addJobCreator(new MyJobCreator());
}
}
Create the following two classes YourJobCreator and YourSyncJob(Where all the work will be done. Android allocates time for all the background jobs to be run. For android versions < 8.0 it will still run with an Alarm manager and background service as per normal)
public class MyJobCreator implements JobCreator {
#Override
#Nullable
public Job create(#NonNull String tag) {
switch (tag) {
case MySyncJob.TAG:
return new MySyncJob();
default:
return null;
}
}
}
public class MySyncJob extends Job {
public static final String TAG = "my_job_tag";
#Override
#NonNull
protected Result onRunJob(Params params) {
//
// run your job here
//
//
return Result.SUCCESS;
}
public static void scheduleJob() {
new JobRequest.Builder(MySyncJob.TAG)
.setExecutionWindow(30_000L, 40_000L) //Every 30 seconds for 40 seconds
.build()
.schedule();
}
}

You should schedule your service with alarm manager, first create the pending intent of service:
Intent ii = new Intent(getApplicationContext(), MyService.class);
PendingIntent pii = PendingIntent.getService(getApplicationContext(), 2222, ii,
PendingIntent.FLAG_CANCEL_CURRENT);
Then schedule it using alarm manager:
//getting current time and add 5 seconds to it
Calendar cal = Calendar.getInstance();
cal.add(Calendar.SECOND, 5);
//registering our pending intent with alarmmanager
AlarmManager am = (AlarmManager) getSystemService(ALARM_SERVICE);
am.set(AlarmManager.RTC_WAKEUP,cal.getTimeInMillis(), pi);
this will launch your service after 5 seconds of current time. You can make your alarm repeating.

You can use Alarm Manager to start Service at specified time and then repeat alarm in specified interval. When alarm goes on you can start service and connect to server and make what you want

How can we prevent a Service from being killed by OS?

I am using Service in my application and it needs to run until my application is uninstalled, but the problem is it gets killed by OS.
How can we prevent it from being killed by OS? Or if it gets killed can we restart that service again through programmatically?

You may run the service in the foreground using startForeground().
A foreground service is a service that's considered to be something
the user is actively aware of and thus not a candidate for the system
to kill when low on memory.
But bear in mind that a foreground service must provide a notification for the status bar (read here), and that the notification cannot be dismissed unless the service is either stopped or removed from the foreground.
Note: This still does not absolutely guarantee that the service won't be killed under extremely low memory conditions. It only makes it less likely to be killed.

I've been puzzled by the same issue to yours recently.but now,I've found a good solution.
First of all,you should know that, even your service was killed by OS, the onCreate method of your service would be invoked by OS in a short while.So you can do someting with the onCreate method like this:
#Override
public void onCreate() {
Log.d(LOGTAG, "NotificationService.onCreate()...");
//start this service from another class
ServiceManager.startService();
}
#Override
public void onStart(Intent intent, int startId) {
Log.d(LOGTAG, "onStart()...");
//some code of your service starting,such as establish a connection,create a TimerTask or something else
}
the content of "ServiceManager.startService()" is:
public static void startService() {
Log.i(LOGTAG, "ServiceManager.startSerivce()...");
Intent intent = new Intent(NotificationService.class.getName());
context.startService(intent);
}
However, this solution is just available for the situation of your service being killed by GC.Sometimes our service might be killed by user with Programme Manager.In this situation,your prosses will be killed,and your service will never been re-instantiated.So your service can not be restarted.
But the good news is,when the PM kill your service,it will call your onDestroy method.So we can do something with that method.
#Override
public void onDestroy() {
Intent in = new Intent();
in.setAction("YouWillNeverKillMe");
sendBroadcast(in);
Log.d(LOGTAG, "onDestroy()...");
}
The string of "YouWillNeverKillMe" is a custom action.
The most important thing of this method is,don't add any code before send the broadcast.As system will not wait for completion of onDestroy(),you must send out the broadcast as soon as posible.
Then regist a receiver in manifast.xml:
<receiver android:name=".app.ServiceDestroyReceiver" >
<intent-filter>
<action android:name="YouWillNeverKillMe" >
</action>
</intent-filter>
</receiver>
Finally,create a BroadcastReceiver,and start your service in the onReceive method:
#Override
public void onReceive(Context context, Intent intent) {
Log.d(LOGTAG, "ServeiceDestroy onReceive...");
Log.d(LOGTAG, "action:" + intent.getAction());
Log.d(LOGTAG, "ServeiceDestroy auto start service...");
ServiceManager.startService();
}
Hope this will be helpful to you,and excuse my poor written english.

Override method onStartCommand() in your service class and simply return START_STICKY (as suggested by "Its not blank"). That's all you need. If the process that runs your service gets killed (by a low memory condition for example), the Android system will restart it automatically (usually with some delay, like 5 seconds).
Don't use onStart() anymore as suggested in another answer, it's deprecated.

use
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
//**Your code **
// We want this service to continue running until it is explicitly
// stopped, so return sticky.
return START_STICKY;
}
ref Documentation lifecycle of Service.
Edit added method.

As far i know, onDestroy() will be called only when the service is explicitly stopped(Force Stop). But this method won't get called in case the service gets killed by OS/swiping the Recent Apps list. In those cases another event handler named onTaskRemoved(Intent) gets called. This is due to a defect in Android 4.3-4.4 as per the link here. Try using the below code:-
public void onTaskRemoved(Intent intent){
super.onTaskRemoved(intent);
Intent intent=new Intent(this,this.getClass());
startService(intent);
}

I found another solution of the problem which gurantees that your service will be always alive. In my case, this scheme resloves also the problem with FileObserver, which stops work after some period of time.
Use an activity (StartServicesActivity) to start the service (FileObserverService) as Foreground service.
Use BroadcastReceiver class (in example CommonReceiver) to restart your service in some special situations and in case it was killed.
I used this code in my app "Email Pictures Automatically"
https://play.google.com/store/apps/details?id=com.alexpap.EmailPicturesFree
Here is CommonReceiver class.
public class CommonReceiver extends BroadcastReceiver {
public void onReceive(Context paramContext, Intent paramIntent)
{
paramContext.startService(new Intent(paramContext, FileObserverService.class));
}
}
Here is its definition in AndroidManifest.xml just before application closing tag.
<receiver android:name="com.alexpap.services.CommonReceiver">
<intent-filter>
<action android:name="android.intent.action.BOOT_COMPLETED"/>
</intent-filter>
<intent-filter>
<action android:name="android.net.conn.CONNECTIVITY_CHANGE"/>
</intent-filter>
<intent-filter>
<action android:name="android.intent.action.USER_PRESENT"/>
</intent-filter>
</receiver>
Start service in StartServicesActivity activity.
Intent iFileObserver = new Intent(StartServicesActivity.this, FileObserverService.class);
StartServicesActivity.this.startService(iFileObserver);
Here is onStartCommand() method of the service.
public int onStartCommand(Intent intent, int flags, int startId) {
int res = super.onStartCommand(intent, flags, startId);
/*** Put your code here ***/
startServiceForeground(intent, flags, startId);
return Service.START_STICKY;
}
public int startServiceForeground(Intent intent, int flags, int startId) {
Intent notificationIntent = new Intent(this, StartServicesActivity.class);
notificationIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, notificationIntent, 0);
Notification notification = new NotificationCompat.Builder(this)
.setContentTitle("File Observer Service")
.setContentIntent(pendingIntent)
.setOngoing(true)
.build();
startForeground(300, notification);
return START_STICKY;
}
I tested this code using Task Killer app, and each time the service was killed, it was restarted again almost immediately (performs onStartCommand()). It is restarted also each time you turn on the phone and after rebooting.
I use this code in my application, which emails every picture you take with your phone to predefinde list of emails. The sending email and list of receiving emails are set in another activity and are stored in Shared Preferences. I took about 100 pictures in several hours and all they were sent properly to receiving emails.

#Override
public void onDestroy() {
super.onDestroy();
startService(new Intent(this, YourService.class));
}
write above code in your service and your service will never stop even user want to destroy it or they want to kill it it will never kill untill your app not get uninstall from your device

You can try to start your service repeatedly, for example every 5 sec.
This way, when your service is running, it will perform onStartCommand() every 5 sec. I tested this scheme and it is very reliable, but unfortunately it increases slightly phone overhead.
Here is the code in your activity where you start the service.
Intent iFileObserver = new Intent(StartServicesActivity.this, FileObserverService.class);
PendingIntent pendingIntentFileObserver = PendingIntent.getService(StartServicesActivity.this, 0, iFileObserver, 0);
AlarmManager alarmManager = (AlarmManager)getSystemService(ALARM_SERVICE);
Date now = new Date();
//start every 5 seconds
alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, now.getTime(), 5*1000, pendingIntentFileObserver);
And here is onStartCommand() of the service.
//class variable
public static boolean isStarted = false;
public int onStartCommand(Intent intent, int flags, int startId) {
int res = super.onStartCommand(intent, flags, startId);
//check if your service is already started
if (isStarted){ //yes - do nothing
return Service.START_STICKY;
} else { //no
isStarted = true;
}
/**** the rest of your code ***/
return Service.START_STICKY;
}

First create service in another process, and write broadcaster which runs in recursion in time intervals
protected CountDownTimer rebootService = new CountDownTimer(9000, 9000) {
#Override
public void onTick(long millisUntilFinished) {
}
#Override
public void onFinish() {
sendBroadcast(reboot);
this.start();
Log.d(TAG, "rebootService sending PREVENT AUTOREBOT broadcast");
}
};
After that register broadcast receiver in main process also with timer recursion that is launched after first broadcast from service arrived
protected static class ServiceAutoRebooter extends BroadcastReceiver {
private static ServiceAutoRebooter instance = null;
private RebootTimer rebootTimer = null;
private static ServiceAutoRebooter getInstance() {
if (instance == null) {
instance = new ServiceAutoRebooter();
}
return instance;
}
public class RebootTimer extends CountDownTimer {
private Context _context;
private Intent _service;
public RebootTimer(long millisInFuture, long countDownInterval) {
super(millisInFuture, countDownInterval);
}
#Override
public void onTick(long millisUntilFinished) {
}
#Override
public void onFinish() {
_context.startService(_service);
this.cancel();
Log.d(TAG, "Service AutoRebooted");
}
}
#Override
public void onReceive(Context context, Intent intent) {
if (rebootTimer == null) {
Log.d(TAG, "rebootTimer == null");
rebootTimer = new RebootTimer(10000, 10000);
rebootTimer._context = context;
Intent service = new Intent(context, SomeService.class);
rebootTimer._service = service;
rebootTimer.start();
} else {
rebootTimer.cancel();
rebootTimer.start();
Log.d(TAG, "rebootTimer is restarted");
}
}
}
Service will be auto-rebooted if time at RebootTimer (main process) expires, which means that "PREVENT AUTOREBOT" broadcast from service hasn't arrived

i found a solution .... late answer but i wanted to answer...
we can send a broadcast in the ondestroy of the service and create a receiver that receives the broadcast and starts the service again.... when it is destroyed by any reasons...

pls try following:
final Messenger mMessenger = new Messenger(new IncomingHandler());
class IncomingHandler extends Handler {
#Override
public void handleMessage(Message msg) {
switch (msg.what) {
default:
super.handleMessage(msg);
}
}
}
#Override
public void onCreate() {
super.onCreate();
makeServiceForeground();
}
#Override
public IBinder onBind(Intent arg0) {
return mMessenger.getBinder();
}
private void makeServiceForeground() {
IActivityManager am = ActivityManagerNative.getDefault();
try {
am.setProcessForeground(onBind(null), android.os.Process.myPid(), true);
} catch (RemoteException e) {
Log.e("", "cant set to foreground" + e.toString());
}
}
also need add in manifest.xml
<uses-permission android:name="android.permission.SET_PROCESS_LIMIT"/>