Android service being stopped, how to notify applications? - android

I have an application which works like a framework - other apps can register a PendingIntent with my app which triggers them at some point in the future. I am keeping the PendingIntents in an array list in a service and then iterating over them to trigger. To register an intent the application calls "startService()" with a PendingIntent set within the intent bundle.
At some point, my service is being closed - or more specifically my array list is being emptied (which can only happen by Android killing the service) and as such I loose my PendingIntents for the registered apps.
How can I keep my service alive, or more specifically keep my PendingItents from being lost? I don't want to go against the Android system mechanisms and create a hacky effort, I would like to know the way in which Google think this should be done.

When a service is killed, it's onDestroy() method is called. You could probably over-ride the onDestroy() method and do something like:
public void onDestroy(){
Intent intent = new Intent();
intent.setAction("SERVICESTOPPED");
sendBroadcast(intent);
super.onDestroy();
}
Have a BroadcastReceiver that listens to this intent and handle the situation as and when it happens.
Alternatively, in the onstartCommand(), if you specify the return value as START_STICKY, the OS will restart your service if it gets killed by OS. Generally this happens with long running serices

Have you tried with START_STICKY?
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
// Put your code here
return START_STICKY;
}
You can try START_REDELIVER_INTENT

Related

Stop the Service on Destroy of Application

I am confused right now , about service concept of running and stopping:
what i want to do:
Start Location service at the very start of application.
Keep getting location updates and store them to shared preference
Stop the service in onDestroy of Application scope!
So far i have searched and studied we can only do following things with service(correct me if i'm wrong):
Stop the service automatically by binding it to related activities/fragments/views , when all of them destroyed service unbind itself automatically so we can call stopself method in unbind
return START_NOT_STICKY in onStartCommand to tell OS , don't recreate it , and create intent local service , after completion of some work it will destroy itself.
Stopping the service manually , by declaring it's intent in some kind of static scope and stopping the service in on onActivityDestroyed of Application class [I am not sure what will happen? , maybe service will destroy each time any activity will be destroyed ? or it will be destroyed only when overall application get's destroyed?]
Either way , i am bit confused and beat , been trying to adjust my Location service with given details for 2 days
If you start your Service using START_NOT_STICKY, then your app will kill your service once your entire application is closed from background i.e. you cleaned your app from home screen.
Here START_NOT_STICKY states that you need not recreate service in case it is been killed.
If this is not the case then you have to manually kill it by your self.
Like
Intent lintent = new Intent(context, LocationService.class);
context.stopService(lintent);
You can use this code at point where your application kills.
That's it. You are good to go with this.
First of all, launch the "LocationService" on your app start:
public class MyApp extends Application {
private static final String TAG = "MyApp";
#Override
public void onCreate() {
super.onCreate();
Log.d(TAG, "App started up");
startService(new Intent(this, MyLocationService.class));
}
}
Second :
As you said, the Service should better run with the "START_NOT_STICKY" flag
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
return START_NOT_STICKY;
}
Thrid:
Once the system kills your app, the Service will automatically be killed, so no problems at all.
There is no onDestroy() method on the Application object, the only similar event is onTerminated() and it is not being launched on production devices.
onTerminate
Added in API level 1 void onTerminate () This method is for use in
emulated process environments. It will never be called on a production
Android device, where processes are removed by simply killing them; no
user code (including this callback) is executed when doing so.
More information:
https://developer.android.com/reference/android/app/Application.html#onTerminate()
Btw, If you want the MyLocationService to send updates of the location to your app (when it is open), you should consider to use Otto or EventBus (I recommend you this last one because of the simplicity to use it). You can even configure the #Suscriber to receive updates of old retrieved locations if you want.
I will try to explain in a easiest way :)
There are two type of service
IntentService and Service
IntentService when started will kill itself once it treated the content of it onHandleIntent method
as for Service well this one will not end until you give it the command to do so even if your start it using the context of an activity. It will also stop when the application is stopped in an extreme case (by system (Settings/application/YourApp/stop app OR an app crash)
Easiest way is First of all start IntentService with AlarmManager at some repeating time (10 mintutes), then in onHandleIntent() get Location and store into preference.
No Need bind to your activity, the IntentService automatically stops itself after saved in preferences.
Yes you can stop the service in onDestroy() of the activity:
#Override
public void onDestroy(){
Log.v("SERVICE","Service killed");
service.stop();
super.onDestroy();
}

How to automatically restart a service even if user force close it?

I want a service to run all the time in my application. So I want to restart it even if it is force closed by user. There is definitely a way to do it as apps like facebook are doing it. It's not done using push notification, facebook restarts its service even if internet is off.
First of all, it is really very bad pattern to run service forcefully against the user's willingness.
Anyways, you can restart it by using a BroadcastReceiver which handles the broadcast sent from onDestroy() of your service.
StickyService.java
public class StickyService extends Service
{
private static final String TAG = "StickyService";
#Override
public IBinder onBind(Intent arg0) {
// TODO Auto-generated method stub
return null;
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.e(TAG, "onStartCommand");
return START_STICKY;
}
#Override
public void onDestroy() {
super.onDestroy();
sendBroadcast(new Intent("YouWillNeverKillMe"));
}
}
RestartServiceReceiver.java
public class RestartServiceReceiver extends BroadcastReceiver
{
private static final String TAG = "RestartServiceReceiver";
#Override
public void onReceive(Context context, Intent intent) {
Log.e(TAG, "onReceive");
context.startService(new Intent(context.getApplicationContext(), StickyService.class));
}
}
Declare the components in manifest file:
<service android:name=".StickyService" >
</service>
<receiver android:name=".RestartServiceReceiver" >
<intent-filter>
<action android:name="YouWillNeverKillMe" >
</action>
</intent-filter>
</receiver>
Start the StickyService in a Component (i.e. Application, Activity, Fragment):
startService(new Intent(this, StickyService.class));
OR
sendBroadcast(new Intent("YouWillNeverKillMe"));
You have to create a sticky service with overriding onTaskRemoved method, where you can set an alarm service to trigger your code again.
public class BackgroundService extends Service {
#Nullable
#Override
public IBinder onBind(Intent intent) {
return null;
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
return START_STICKY;
}
#Override
public void onTaskRemoved(Intent rootIntent) {
//create an intent that you want to start again.
Intent intent = new Intent(getApplicationContext(), BackgroundService.class);
PendingIntent pendingIntent = PendingIntent.getService(this, 1, intent, PendingIntent.FLAG_ONE_SHOT);
AlarmManager alarmManager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
alarmManager.set(AlarmManager.RTC_WAKEUP, SystemClock.elapsedRealtime() + 5000, pendingIntent);
super.onTaskRemoved(rootIntent);
}
}
Also in some devices like Xiaomi, Huwaei the app gets force closed once it's removed from recent apps. This is because the manufacturers have task manager features which improve ram/battery performance.
You can check this link for more information: https://stackoverflow.com/a/41360159/2798289
As per the Android document
Starting from Android 3.1, the system's package manager keeps track of applications
that are in a stopped state and provides a means of controlling their launch from
background processes and other applications.
Note that an application's stopped state is not the same as an Activity's stopped
state. The system manages those two stopped states separately.
FLAG_INCLUDE_STOPPED_PACKAGES — Include intent filters of stopped applications in the
list of potential targets to resolve against.
FLAG_EXCLUDE_STOPPED_PACKAGES — Exclude intent filters of stopped applications from the
list of potential targets.
When neither or both of these flags is defined in an intent, the default behavior is to
include filters of stopped applications in the list of potential targets.
Note that the system adds FLAG_EXCLUDE_STOPPED_PACKAGES to all broadcast intents.
It does this to prevent broadcasts from background services from inadvertently or
unnecessarily launching components of stopped applications. A background service
or application can override this behavior by adding the FLAG_INCLUDE_STOPPED_PACKAGES
flag to broadcast intents that should be allowed to activate stopped applications.
On Force stop of app, Android just kill the process ID. No warnings, callbacks are given to service/activities. As per the Android document, When the app is killed there are chances that it calls onPause().
When I tried in my app, even onPause() was not called. I think the only way is use to FLAG_INCLUDE_STOPPED_PACKAGES intent flag and send it from another app
If I understand correctly, then actually this is not possible, Android feature to force close application was designed to allow user to get rid of unwanted applications, so it disallows any activities from it until user again starts any of its Activity.
Restart the service even if app is force-stopped and Keep running service in background even after closing the app How?
Whenever a service is killed, its onDestroy method is always called.
Its better to use a BroadcastReceiver to start your service when it is killed.
Here is a sample code illustrating its implementation:-
#Override
public void onDestroy() {
Intent in = new Intent();
in.setAction("StartkilledService");
sendBroadcast(in);
Log.d("debug", "Service Killed");
}
Then register a receiver in AndroidManifest.xml:-
<receiver android:name=".app.ServiceDestroyReceiver" >
<intent-filter>
<action android:name="StartKilledService" >
</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("debug", "ServeiceDestroy onReceive...");
Log.d("debug", "action:" + intent.getAction());
Log.d("debug", "Starting Service");
ServiceManager.startService();
}
Hope this helps.
on the service's startCommand method return START_STICKY. generally it tell the OS to start the service when it is killed.
If the situation allows to use 'root' it's usually possible to implement Humpty-Dumpty paradigm.
Your application (1st) installs another application (2nd, taking APK from assets) and runs the service of the 2nd app.
2nd app's service bind to the 1st app service and rebinds when disconnected. The 1st app does the same.
Sure it will not help when all apps are killed by some Free RAM or similar application but when Android kills either of those two, the other one will restart its counterpart.
The only real solution for keeping services alive ist to call Service.startForeground(...) with a provided Notification. This will be the only valid solution, every other one will be very dependent on how Google will change the behaviour of it's system. With every API update, Google could prevent every other hack.
This also keeps the user aware, that your app is performing some background task which will keep the app alive and the user has to stop this. If you provide the user the ability to stop it is part of your application, though.
See the Documentation:
void startForeground (int id, Notification notification)
Make this service run in the foreground, supplying the ongoing notification to be shown to the user while in this state. By default services are background, meaning that if the system needs to kill them to reclaim more memory (such as to display a large page in a web browser), they can be killed without too much harm. You can set this flag if killing your service would be disruptive to the user, such as if your service is performing background music playback, so the user would notice if their music stopped playing.
There is a very hacky solution to keep service running even you force stop it. I do not recommend that because it is against user willingness. You can define a broadcast receiver to receive intent with action X. onStartCommand handler of your service, broadcast X (if the service is not started yet). on broadcast receiver upon receipt of X, first start the service, then, sleep for some minutes, and finally re-broadcast X.
I think the only foolproof solution here is to have 2 services in separate processes (android:process="somecustomprocessname" in manifest, in the service entry) that both listen to broadcasts and restart each other, because currently the UI doesn't let users kill multiple processes in one action. You can then set up a pinger thread in each service that checks if the other service is running every 100 milliseconds or so, and if not, attempts to restart it. But this is starting to look more and more like malware...

Foreground service killed when user swypes away

As the title says I am having the following problem. My foreground service is being killed when the activity that started it is swyped away from recent tasks list.
I am starting a service with
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
startForeground(notificationID, notification);
return START_STICKY;
}
Can someone please tell me why is this happening and how can I make it so the service stays running when user swypes the activity away.
I don't have access to public void onTaskRemoved (Intent rootIntent) for some reason but I don't know what to do in that method anyway...
I am starting the service like this this and it's not a bound service
serviceIntent = new Intent(this, RecordingService.class);
startService(serviceIntent);
If little use case description helps I am trying to control sound recorder from a remote view in the notification bar so restarting a service is not an option since it should continue to record even if activity is destroyed.
BTW.I did tried starting a service in another process by android:process=":recordingProcess" and the service does continue to run then but I am suspecting this is not how you should do it.
Even i had the same issue and i had access to onTaskRemoved() function.Please check this link, "Process life cycle" topic.
Try to return from onStartCommand() START_REDELIVER_INTENT, service will get start again.
From Android Developer Reference
A service can be both started and have connections bound to it. In
such a case, the system will keep the service running as long as
either it is started or there are one or more connections to it with
the Context.BIND_AUTO_CREATE flag. Once neither of these situations
hold, the service's onDestroy() method is called and the service is
effectively terminated.
How are you starting your service?

IntentService not firing

My application synchronizes data with a remote database via web service calls. I make these calls in an IntentService so they can run in the background (I call it SyncService).
The code to launch my IntentService looks like so:
Intent intent = new Intent();
intent.setClass(appContext, SyncService.class);
// place additional values in intent
intent.putExtra("data_type", SyncService.ITEM_TRACKING);
intent.putExtra("user_id", intUserId);
// call SyncService
appContext.startService(intent);
This, normally, looks great. However, one of my friends, who is also a user of my app, often tells me his data doesn't sync and get displayed on our website. His device happened to be displaying the symptoms while I was around. I plugged his device into my computer and here is what I found:
The code to launch SyncService (ie: the code above) was hit.
I had a breakpoint inside the onHandleIntent method of my IntentService and it never gets hit.
I checked his device's list of running services and SyncService was there and running. Interestingly, it had been running for about 20 minutes. I was under the impression that IntentService killed itself when it was all out of Intents to process.
I force stopped the SyncService (not the app) and, all of the sudden, onHandleIntent started getting hit over and over. It was like all the Intents were queued up somewhere on the device and were just now getting thrown at the SyncService.
Does anyone have any ideas as to what may be the problem? Do you think it's an issue with my app? With Android?
Again, I am handing a message to Android saying, "Start this IntentService or send the message to the already running IntentService." At that point, I have no control. The message never gets to the IntentService. Once I force quit the app, the messages get sent to the IntentService and it does its job.
UPDATE: I think this code is fine, but I'll put it up since a lot of you may want to see it.
Every Intent that comes in to the IntentService has an Extra denoting what "type" of call is to me made (ie: do I call this web service or that web service, etc). When an Intent comes in to the IntentService, I check the "type" and, if there is already an Intent in the queue for that type, I add an Extra to it called "skip" so, when it is reached, I don't execute the search (basically the IntentService can build up lots of Intents and it makes no sense to call this web service when this webservice was called 20 seconds ago). It basically protects the app from spamming the website.
It is important to note that none of this code is hit anyway (once the problem starts occurring). onStartCommand does not get called until the app is killed
#Override
public int onStartCommand (Intent intent, int flags, int startId) {
// here be dragons
// overriding this method and adding your own code is dangerous. i've wrapped
// my code in a try/catch because it is essential that the super method be called
// every time this method is entered. any errors in my code should not prevent this
// or the app will explode.
try {
if (flags == 0 && intent != null && intent.hasExtra("data_type")) {
Integer intDataType = intent.getExtras().getInt("data_type");
if (!mCurrentTypes.containsKey(intDataType)
|| !mCurrentTypes.get(intDataType)) {
mCurrentTypes.put(intDataType, true); // put this type in the list and move on
}
else {
intent.putExtra("skip", true); // mark this Intent to be skipped
}
}
}
catch (Exception e) {
// Log.e("Error onStartCommand", "error: " + e);
}
return super.onStartCommand(intent, flags, startId);
}
private void processIntent(Intent intent) {
// do stuff if no "skip" Extra
mCurrentTypes.put(intDataType, false);
}
There is definitly something that keeps your service running on your friend's device. If so all subsequent call to this intent service are queued until the current one finishes. If it doesn't finish then you will get what you have : next services won't start.
You should double check that :
you give proper timeouts to nework operations
you give proper timeouts to nework connections operations
there is no race condition between threads.
you log any exception that can occur inside the service, you don't wanna loose that kind of information.
Afterwards, if you think everything is green : just log what the service does and use some bug reporting mechanism to get it automatically sent from your friends device. A simple solution could be to use bugsense or equivalent.
Next, put in place some kind of watchdog : a thread that will go on running until your service stops (you just tell your thread to stop when service is stopped). The thread will have to stop your service after some time limit has been passed.
This watchdog thread could be put inside the service itself, or outside, although this may be more complex to put in place.
This answer suggests a solution that worked for me in similar situations. It doesn't fix your current code but suggests another, perhaps simpler (and easier to debug) option:
Add a BroadcastReceiver to your calling Activity that listens for SUCCESS Intents from the IntentService.
In your calling Activity, include the logic for when to start the IntentService (and don't include it in the IntentService). The logic is:
Call startService() and set a flag in the calling Activity to CANNOT_CALL.
If the Activity's BroadcastReceiver has not received a SUCCESS broadcast from the IntentService, then startService() can not be called again.
When the Activity does receive a SUCCESS intent, set the flag to CAN_CALL, and startService() can be called when the timer hits again.
In your IntentService, write your onStartCommand() like so:
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
super.onStartCommand(intent, flags, startId);
return START_STICKY;
}
In you IntentService, when you've received, parsed and stores the web service response, call sendBroadcast() with an Intent with custom action SUCCESS.
This logic is just an outline and has to be fine-tuned for error messages from the web service that have to be broadcast from IntentService to the listening Activity.
Hope this helps.
It seems to me that setting a set of flags to your Intent may solve the problem.
Intent intent = new Intent();
intent.setClass(appContext, SyncService.class);
// This way
intent.setFlags(Intent.FLAG_ACTIVITY_MULTIPLE_TASK|Intent.FLAG_ACTIVITY_NEW_TASK|Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS);
You can make your Service start as fresh using the above flag in a fresh task.
One more comment. It's not an answer for your question. However, it may affect overall behavior of a service.
You do following:
return super.onStartCommand(intent, flags, startId);
Internally Service.onStartCommand() looks like following
public int onStartCommand(Intent intent, int flags, int startId) {
onStart(intent, startId);
return mStartCompatibility ? START_STICKY_COMPATIBILITY : START_STICKY;
}
mStartCompatibility is false if your app target SDK API 7 or later (which is most likely a case).
So, as result your service will be started as START_STICKY.
Here is piece from documentation:
For started services, there are two additional major modes of operation they can decide to run in, depending on the value they return from onStartCommand(): START_STICKY is used for services that are explicitly started and stopped as needed, while START_NOT_STICKY or START_REDELIVER_INTENT are used for services that should only remain running while processing any commands sent to them. See the linked documentation for more detail on the semantics.
Base on what you have described, I recommend to replace "return super.onStartCommand(intent, flags, startId);" to "return START_NOT_STICKY;"

android long running service without notification

I see this example with programs like Advance Task killer, Watch Dog, eBay, battery widgets, ect. There is a background service running that monitors device activity, a broadcastreceiver, but there is an option to disable the notification icon displayed. Currently my application works flawlessly by calling:
Context context = getApplicationContext();
Intent intent = new Intent(context, SomeBackGroundService.class);
context.startService(intent)
and then in my service I am calling:
startForeground(NOTIFICATION_ID, notification);
Now how is it that these other applications can have a long running broadcastreceiver running without a notification icon? What do I need to do in order to disable/set ect as to hide the icon and add this feature to my application?
Thanks in advance
I'm not expert on this, but I disagree with the accepted answer.
Your startForeground is key to ensuring that your service continues running.
Without that, it might keep running, but it has a much lower priority so it is much more likely to be killed by the system.
Your service is entirely independent of whether or not a notification exists for it. If you removed the line, startForeground, the service would continue to run. The only time a service stops is if you call context.stopService() or stopSelf(). Throw some logs into your service, and you'll see that it continues to run.
Override the onStartCommand to determine behavior of your service after garbage collection:
#Override
public int onStartCommand(Intent intent, int flags, int startId() {
super.onStartCommand(intent, flags, startId);
doWork();
return START_STICKY;
}
START_STICKY recreates your service after garbage collection. START_REDELIVER_INTENT will recreate your service after garbage collection using the original intent, use this only if you need extra intent data.
Create a notification that contains an icon made with a png and is only 1 pixel in height and width and make that pixel transparent.

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