Develop Reference

Android Listener stop running when app in background

I am developing an app where the app will detect Bluetooth signals (Sensoro Smart Beacon device) and open the activity. But I want the app to still be able to detect the signal even when the application on the background or even when killed. I used a foreground service, it detects the signal when I open the application and move between activities but when sending the app to the background and opening other applications, the listener stops although the service still working. I am printing the logs. System.out.println("Sensoro 2" ); keeps printing even when I kill the application or open another application. But the printing logs in BeaconManagerListener are not working. I tried to use background service but it didn't work also.
Can you please advise if there is a way to make the listener works in a service when the app in background or killed?
Here is the service code:
public class MyService extends Service {
public static final String CHANNEL_ID = "ForegroundServiceChannel";
int service_timer=0;
Timer timer = new Timer();
SensoroManager sensoroManager;
#Override
public void onCreate() {
super.onCreate();
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
sensoroManager = SensoroManager.getInstance(MyService.this);
String input = intent.getStringExtra("inputExtra");
System.out.println("Sensoro 2" );
createNotificationChannel();
Intent notificationIntent = new Intent(this, MainActivity.class);
PendingIntent pendingIntent = PendingIntent.getActivity(this,
0, notificationIntent, 0);
Notification notification = new NotificationCompat.Builder(this, CHANNEL_ID)
.setContentTitle("Foreground Service")
.setContentText(input)
.setSmallIcon(R.drawable.ic_launcher_background)
.setContentIntent(pendingIntent)
.build();
startForeground(1,notification);
//do heavy work on a background thread
//stopSelf();
if (sensoroManager.isBluetoothEnabled()) {
sensoroManager.setCloudServiceEnable(true);
/**
* Enable SDK service
**/
try {
sensoroManager.startService();
} catch (Exception e) {
e.printStackTrace(); // Fetch abnormal info
}
}
else
{
Toast.makeText(MyService.this,"Bluetooth off",Toast.LENGTH_LONG).show();
}
new Timer().scheduleAtFixedRate(new TimerTask() {
#Override
public void run() {
//your method
System.out.println("Sensoro 2" );
BeaconManagerListener beaconManagerListener = new BeaconManagerListener() {
#Override
public void onUpdateBeacon(ArrayList<Beacon> beacons) {
// Refresh sensor info
for (Beacon beacon : beacons
) {
System.out.println("Sensoro 3" );
// System.out.println("Sensoro" +beacon.getAccuracy());
}
}
#Override
public void onNewBeacon(Beacon beacon) {
if (beacon.getSerialNumber().equals("0117C59B243C")){
System.out.println("Sensoro 3" );
System.out.println("Sensoro acc" +beacon.getAccuracy());
}
}
#Override
public void onGoneBeacon(Beacon beacon) {
if (beacon.getSerialNumber().equals("0117C59B243C")){
System.out.println("Sensoro acc gone");
System.out.println("Sensoro acc Timer" +service_timer);
}
}
};
sensoroManager.setBeaconManagerListener(beaconManagerListener);
}
}, 0, 2000);
return START_NOT_STICKY;
}
#Override
public void onDestroy() {
super.onDestroy();
// timer.cancel();
}
#Nullable
#Override
public IBinder onBind(Intent intent) {
return null;
}
private void createNotificationChannel() {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
NotificationChannel serviceChannel = new NotificationChannel(
CHANNEL_ID,
"Foreground Service Channel",
NotificationManager.IMPORTANCE_DEFAULT
);
NotificationManager manager = getSystemService(NotificationManager.class);
manager.createNotificationChannel(serviceChannel);
}
}
}
Here is where I call it:
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
startService();
}
public void startService() {
Intent serviceIntent = new Intent(this, MyService.class);
serviceIntent.putExtra("inputExtra", "Foreground Service Example in Android");
System.out.println("Sensoro 1 ");
ContextCompat.startForegroundService(this, serviceIntent);
}
public void stopService() {
Intent serviceIntent = new Intent(this, MyService2.class);
stopService(serviceIntent);
}
public void movingg(View view) {
Intent intent=new Intent(this,Usermain.class);
startActivity(intent); }
}

This is not 100% a match with what are you searching but this is near to what are you want.
You can use WorkManager that is working even application in the background. There are two types of WorkManager. 1) OneTimeWorkRequest 2) PeriodicWorkRequest.
So you can you PeriodicWorkRequest which will call every 15 min(minimum interval) and you can add your code in WorkManager to detect Bluetooth signals. So you can able to detect Bluetooth single at every 15 mins of intervals.
I hope this will help you solve your problem.

I don't know if this will help you, but here's my answer:
public void startService() {
Intent serviceIntent = new Intent(this, MyService.class);
serviceIntent.putExtra("inputExtra", "Foreground Service Example in Android");
System.out.println("Sensoro 1 ");
startService(serviceIntent);
}

I looked at the Android rules and regulations page
According to Google documents, from Android 8 onwards, all applications that do not have a Google-approved signature will be removed from the background after a few minutes.
But the solutions:
The first solution is to run the application in debug mode
The second solution is to assign a signature to the application and send it to Google for approval
recommend:
The third solution is to remove the google play service application from the emulator or android phone

you can use BroadcastReceiver.
if your app is killed or in the background ,the broadcast receiver is catch the event of bluetoth

I see there are two issues with your approach here.
First you should your check for specific beacon serial number could be causing issue.
Secondly you are using a Timer that goes off every 2 seconds and every time it does it adds a new BeaconManagerListener which should not be the case you should extract the listener outside maybe make it a class member and then use the same listener every time instead of continuously creating new listener which then replaces the old one.
Also why add listener after 2 seconds I think is should be added before calling sensoroManager.startService()
Lastly if the task is not needed to be repeated every few seconds and can be done with an interval >= 15 mins then consider using Periodic Work Manager instead.

android service file read

I'm trying to make an Android App that records the user's activity(like where he touches or drags).
Because of the recent change in Android security and permissions, we can't make an app that draws over an another app and records its movements.
So our team decided to solve the problem this way
since the adb shell's permission is root, we can use logcat and the grep tool to parse the logs and find what we want.
create a service that constantly spins up logcat and saves into a file.
create another service that reads the file logcat created, parse, and show the info.
There is currently a problem in our team.
How can we make a service that constantly reads a file and spit out the results?
After that we can do the other jobs more easily.

You can create a service as mentioned in below step to keep the service running all the time
1) In the service onStartCommand method return START_STICKY.
public int onStartCommand(Intent intent, int flags, int startId) {
return START_STICKY;
}
2)Start the service in the background using startService(MyService) so that it always stays active regardless of the number of bound clients.
Intent intent = new Intent(this, PowerMeterService.class);
startService(intent);
3)Create the binder.
public class MyBinder extends Binder {
public MyService getService() {
return MyService.this;
}
}
4)Define a service connection.
private ServiceConnection m_serviceConnection = new ServiceConnection() {
public void onServiceConnected(ComponentName className, IBinder service) {
m_service = ((MyService.MyBinder)service).getService();
}
public void onServiceDisconnected(ComponentName className) {
m_service = null;
}
};
5)Bind to the service using bindService.
Intent intent = new Intent(this, MyService.class);
bindService(intent, m_serviceConnection, BIND_AUTO_CREATE);
6)For your service you may want a notification to launch the appropriate activity once it has been closed.
private void addNotification() {
// create the notification
Notification.Builder m_notificationBuilder = new Notification.Builder(this)
.setContentTitle(getText(R.string.service_name))
.setContentText(getResources().getText(R.string.service_status_monitor))
.setSmallIcon(R.drawable.notification_small_icon);
// create the pending intent and add to the notification
Intent intent = new Intent(this, MyService.class);
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent, 0);
m_notificationBuilder.setContentIntent(pendingIntent);
// send the notification
m_notificationManager.notify(NOTIFICATION_ID, m_notificationBuilder.build());
}
7)You need to modify the manifest to launch the activity in single top mode.
android:launchMode="singleTop"
8)Note that if the system needs the resources and your service is not very active it may be killed. If this is unacceptable bring the service to the foreground using startForeground.
startForeground(NOTIFICATION_ID, m_notificationBuilder.build());

Cannot keep android service alive after app is closed

I am trying to spawn a service that stays alive all the time, even if the user closes the application. According to these threads
Keep location service alive when the app is closed
Android Service Stops When App Is Closed
Android: keep Service running when app is killed
this can be accomplished with IntentServices or Service.START_STICKY
Yet, I tried both types of services without success. In other words, my services get killed when the app is closed by the user. Can someone point out if this is can be done and how? Here is what I have tried without success:
With IntentService:
public class MyIntentService extends IntentService {
private final int mPollingTimeMS = 500;
private int mInitializationPollingCount = 0;
private Thread mPollThread;
public MyIntentService() {
super("MyIntentService");
}
#Override
protected void onHandleIntent(Intent intent) {
mPollThread = new Thread() {
public void run() {
while (true) {
try {
Log.e(Constants.Engine.LOGGER_TAG_DEV,
"SDK Service Running: " +
mInitializationPollingCount * mPollingTimeMS +
"ms have elapsed");
mInitializationPollingCount++;
sleep(mPollingTimeMS);
} catch (Exception e) {
StackTraceElement trace = new Exception().getStackTrace()[0];
Logger.e(Constants.Engine.LOGGER_TAG_APP, "[Exception:" + e.toString() + "]" +
trace.getClassName() + "->" + trace.getMethodName() + ":" + trace.getLineNumber());
}
}
}
};
mPollThread.start();
}
}
and with Services:
public class MyService extends Service {
public MyService() {
}
private final int mPollingTimeMS = 500;
private int mInitializationPollingCount = 0;
private Thread mPollThread;
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
mPollThread = new Thread() {
public void run() {
while (true) {
try {
Log.e(Constants.Engine.LOGGER_TAG_DEV,
"SDK Service Running: " +
mInitializationPollingCount * mPollingTimeMS +
"ms have elapsed");
mInitializationPollingCount++;
sleep(mPollingTimeMS);
} catch (Exception e) {
StackTraceElement trace = new Exception().getStackTrace()[0];
Logger.e(Constants.Engine.LOGGER_TAG_APP, "[Exception:" + e.toString() + "]" +
trace.getClassName() + "->" + trace.getMethodName() + ":" + trace.getLineNumber());
}
}
}
};
mPollThread.start();
return Service.START_STICKY;
}
#Override
public IBinder onBind(Intent intent) {
// I tried to return null here, but this
// service gets killed no matter what.
return null;
}
}
and here is the manifest:
<service
android:name=".mycompany.MyService"
android:enabled="true"
android:exported="true"
android:process=":process1">
</service>
<service
android:name=".mycompany.MyIntentService"
android:process=":process2"
android:exported="false">
</service>
I shall added that I am closing the test app not with a close button, but using the Android OS app manager. See picture below
Lastly, the driver activity (not much there)
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Intent intent1 = new Intent(getBaseContext(), MyService.class);
startService(intent1);
Intent intent2 = new Intent(getBaseContext(), MyIntentService.class);
startService(intent2);
}
}
I also try to add a notification and make it a foreground service but still the same thing. The moment I close the app, everything gets killed. This is what I added:
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
showNotification();
...etc..
private void showNotification() {
Intent notificationIntent = new Intent(this, MainActivity.class);
notificationIntent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0,
notificationIntent, 0);
int iconId = R.mipmap.ic_launcher;
int uniqueCode = new Random().nextInt(Integer.MAX_VALUE);
Notification notification = new NotificationCompat.Builder(this)
.setSmallIcon(iconId)
.setContentText("Context Text")
.setContentIntent(pendingIntent).build();
startForeground(uniqueCode, notification);
}

Here is an example of foreground service that I use and that works, it remains active when the app is closed. Of course, it also must be started, and for that task the app must be running at a first glance, or a receiver of a boot event must be set, but this is another story.
public class MyService extends Service {
static final int NOTIFICATION_ID = 543;
public static boolean isServiceRunning = false;
#Override
public void onCreate() {
super.onCreate();
startServiceWithNotification();
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
if (intent != null && intent.getAction().equals(C.ACTION_START_SERVICE)) {
startServiceWithNotification();
}
else stopMyService();
return START_STICKY;
}
// In case the service is deleted or crashes some how
#Override
public void onDestroy() {
isServiceRunning = false;
super.onDestroy();
}
#Override
public IBinder onBind(Intent intent) {
// Used only in case of bound services.
return null;
}
void startServiceWithNotification() {
if (isServiceRunning) return;
isServiceRunning = true;
Intent notificationIntent = new Intent(getApplicationContext(), MyActivity.class);
notificationIntent.setAction(C.ACTION_MAIN); // A string containing the action name
notificationIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
PendingIntent contentPendingIntent = PendingIntent.getActivity(this, 0, notificationIntent, 0);
Bitmap icon = BitmapFactory.decodeResource(getResources(), R.drawable.my_icon);
Notification notification = new NotificationCompat.Builder(this)
.setContentTitle(getResources().getString(R.string.app_name))
.setTicker(getResources().getString(R.string.app_name))
.setContentText(getResources().getString(R.string.my_string))
.setSmallIcon(R.drawable.my_icon)
.setLargeIcon(Bitmap.createScaledBitmap(icon, 128, 128, false))
.setContentIntent(contentPendingIntent)
.setOngoing(true)
// .setDeleteIntent(contentPendingIntent) // if needed
.build();
notification.flags = notification.flags | Notification.FLAG_NO_CLEAR; // NO_CLEAR makes the notification stay when the user performs a "delete all" command
startForeground(NOTIFICATION_ID, notification);
}
void stopMyService() {
stopForeground(true);
stopSelf();
isServiceRunning = false;
}
}
Then I run it with
Intent startIntent = new Intent(getApplicationContext(), MyService.class);
startIntent.setAction(C.ACTION_START_SERVICE);
startService(startIntent);
Please note the two constants used as Actions, these are Strings that must start with the package name.

IntentService
Using IntentService is probably not the best approach. By default IntentService stops itself after onHandleIntent(Intent) returns and there's no work left to do (i.e. the request queue is empty). This is explained in the official docs of IntentService:
When all requests have been handled, the IntentService stops itself, so you should not call stopSelf().
In your case, onHandleIntent(Intent) creates a thread but returns right away, which makes it stop by itself.
Service + startForeground()
Using a regular Service in foreground mode should work as long as you keep that service running on a separate process. For that, you need:
Make the onStartCommand() return START_STICKY.
Call the method to show the notification right in onCreate().
Run the service in a separate process (using android:process=":something").
Based on the post, it seems that you've tried some of these steps in isolation but never tried all of them at the same time.

If none of the answers above are working, maybe it is a manufacturer specific issue. Some MI phones, for instance, kill the foreground service when the user kill the app via task manager.
I recommend you to test the app on a virtual device, so you can check if it is or isn't this kind of issue.
Hope it helps!

You can simply call your service in your onStop() method inside your activity.
Even when user stops the app the service will still be running.

Try the answers for this similar question: Bad notification for startForeground in Android app

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.

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"/>