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Callback listener when application is killed from recent applications in android

Let me come straight to my issue.
There is an old similar question:
Continue Service even if application is cleared from Recent app. Please go through the link before going ahead.
I have to save some data to the local database before the application is destroyed completely.
I have following issues with onTaskRemoved() method of the service:
onTaskRemoved() method is not triggered every time the application(and hence the service) is stopped from the recent applications screen.
Even if onTaskRemoved() is called every time, the method is not executed completely. I mean if there are 20 statements in the method, only 5 or 10 statements are executed and the method breaks after that. Like if I have 20 System.out.println() statements than only 5 or 10 or 12(any random number) statement prints and method breaks after that.
So I can rely on the method onTaskRemoved() method for cleaning up resources acquired by the application.
This is a blocking issue for my application release. I have tried every trick. Like having at least one activity in the stack(I am calling it GhostActivity) so that if the application is killed from the recent applications screen, we can do clean up in onDestroyed() method the activity. onDestroyed() is called but it has exact same issues like onTaskRemoved() method.
I am stuck on the issue since weeks and it's very annoying. Please let me know if anyone has any solution.

I finally myself got it worked. I used a combination of service and alarm manager. Every-time I want to handle the force close scenario, I start a service in which I run an infinite loop. This loop will iterator every 15 secs. In the loop, I set an alarm 20 secs from the current time. Now if the next iteration of the loop happens the alarm is updated and reset to 20 secs after new current time. In this way, the alarm will trigger only if the service was not destroyed by the user by calling stopService() method.
public class MyIntentService extends IntentService {
public MyIntentService() {
super("My IntentService");
}
private boolean stopped = false;
private Thread runningThread;
private static MyIntentService mInstance;
#Override
public void onCreate() {
super.onCreate();
mInstance = MyIntentService.this;
}
#Override
public int onStartCommand(#Nullable Intent intent, int flags, int startId) {
return super.onStartCommand(intent, flags, startId);
}
#Override
protected void onHandleIntent(Intent intent) {
stopped = false;
runningThread = Thread.currentThread();
while(!this.stopped) {
Intent intent = new Intent("Your_Custom_Broadcast_Action");
AlarmManager alarmManager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
PendingIntent broadcastIntent = PendingIntent.getBroadcast(WifiService.this, CLEAN_UP_ALARM_REQUEST_CODE,
intent, PendingIntent.FLAG_UPDATE_CURRENT);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
alarmManager.setExactAndAllowWhileIdle(AlarmManager.RTC_WAKEUP, System.currentTimeMillis() + 20000, broadcastIntent);
} else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
alarmManager.setExact(AlarmManager.RTC_WAKEUP, System.currentTimeMillis() + 20000, broadcastIntent);
} else {
alarmManager.set(AlarmManager.RTC_WAKEUP, System.currentTimeMillis() + 20000, broadcastIntent);
}
try {
Thread.sleep(15000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
#Override
public void onDestroy() {
super.onDestroy();
mInstance = null;
if (runningThread != null) {
runningThread.interrupt();
}
}
public void stopService() {
AlarmManager alarmManager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
PendingIntent broadcastIntent = PendingIntent.getBroadcast(WifiService.this, CLEAN_UP_ALARM_REQUEST_CODE,
intent, PendingIntent.FLAG_UPDATE_CURRENT);
alarmManager.cancel(broadcastIntent);
stopped = true;
if (runningThread != null)
runningThread.interrupt();
}
public static MyIntentService getActiveInstance() {
return mInstance;
}
}

Android Service with MediaPlayer gets recreated or destroyed

I'm using bound service so that I am able to communicate between an activity and a service.
I'm binding to a service in onStart:
#Override
protected void onStart() {
super.onStart();
Intent bindIntent = new Intent(this, MusicService.class);
bindService(bindIntent, this, BIND_AUTO_CREATE);
}
waiting for service to bind:
#Override
public void onServiceConnected(ComponentName name, IBinder service) {
mMusicService = ((MusicService.LocalBinder) service).getService();
mMusicService.setCallback(this);
}
handling disconnect from service:
#Override
public void onServiceDisconnected(ComponentName name) {
mMusicService = null;
}
unbinding from service in onDestroy:
#Override
protected void onDestroy() {
super.onDestroy();
if (mMusicService != null && isFinishing()) {
mMusicService.setCallback(null);
unbindService(this);
}
}
My problem is that when app is minimized, onDestroy gets called immediately and then onUnbind in Service gets called and music is stopped.
Here is onUnbind method (where mPlayer is MediaPlayer):
#Override
public boolean onUnbind(Intent intent) {
mPlayer.stop();
mPlayer.release();
mPlayer = null;
return super.onUnbind(intent);
}
If I don't implement onUnbind music continues to play (sometimes and sometimes it stops after some time) and when I open the app again (from minimized applications) I am able to play another song and then those two song play at same time.
I've red couple articles about music players and services on android and I thought that this was correct approach (thinking that onDestroy will be called when OS is out of memory).
Any ideas how I can re-implement my app workflow so that I will work as expected?
EDIT
At first I thought that "Don't keep activities" under developer options is a problem, but problem is still there even if I uncheck it.
And if some code from my service is needed please say I will edit my question (there's a lot of code and I'm not sure which part is important for this issue)
SOLUTION:
startForeground(<notification id>, <notification>);
to run service even if app gets killed. And when user dismisses the notification:
stopForeground(true);
stopSelf();
More about startForeground here.

It's not obvious, but you should start a Thread that runs in background and use the service to control it's state.
A service isn't a thread that hold some run state like a thread. Unless it's an IntentService. (Correct me if I'm wrong)
While activity can (and probably will) get destroyed, your app will keep running.
Activity:
#Override
protected void onStart() {
super.onStart();
Intent intent = new Intent(this, BackgroundService.class);
startService(intent);
bindService(intent, mServiceConnection, Context.BIND_AUTO_CREATE);
finishOnPause = true;
}
#Override
protected void onStop() {
super.onStop();
unbindService(mServiceConnection);
}
Service:
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
ensureServiceThread();
if (intent != null) {
}
return START_NOT_STICKY;
}
private void ensureServiceThread() {
if (service_thread == null) {
service_thread = new ServiceThread(this);
service_thread.start();
}
}
#Override
public void onDestroy() {
stopServiceThread();
super.onDestroy();
}
private void stopServiceThread() {
if (service_thread != null) {
service_thread.interrupt();
service_thread = null;
}
}
And you should do your work inside the Thread.
If you need context, it's your Service.
If you need to do something on Main thread - create a Handler in Service.OnCreate and do a handler.postRunnable inside a worker thread safely.
What I would do is:
- Create a service
- Create a thread
- Create a media player inside a thread (if possible, otherwise on Service creation and pass it to thread)
- Inside a thread - continuously poll media player state
- On song finished send an intent to service that change track
- stop thread/service if needed.

app forceclose while running in background

In my android app i have one service which calls some webservices after a fix interval.
App is running perfectly in foreground and refresh data,but when user exit from app and use some other app then my app force close after many times.
Why this app force close while running in background.
Code that i was using for start service -
msgIntent = new Intent(mContext, MyBackgroundService.class);
startService(msgIntent);
and inside onDestroy() of my main activity i have following code to stop service-
if(msgIntent!=null){
stopService(msgIntent);
}
background service call some async task and each aync task onPostExecute() method execute some insert statement in database.
i am not geting why this force close occure.
Please give your comments.
Thanks in advance.
My Service Code
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
callAsynchronousTask();
return Service.START_NOT_STICKY;
}
#Override
public void onCreate() {
mContext = this;
super.onCreate();
}
#Override
public IBinder onBind(Intent intent) {
return null;
}
public void callAsynchronousTask() {
final Handler handler = new Handler();
Timer timer = new Timer();
TimerTask doAsynchronousTask = new TimerTask() {
#Override
public void run() {
handler.post(new Runnable() {
public void run() {
try {
callWebservice();
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
};
timer.schedule(doAsynchronousTask, START_DELAY, DELAY);
}

Actually the problem is here
if(msgIntent!=null){
stopService(msgIntent);
}
in your onDestroy(). Because when you close your application so this above code gets called which is closing your service.
And after closing service again you are trying to insert data by calling service + web service. Hence, there is no service object thats why it gets crashed.
To handle this scenario, you need to comment above code which is in onDestroy() & then check/run it, will solve your problem. & there you need to stop your service by other ways. Go step by step.

you stop the service at onDestroy() method. but services are not depend the activity. So try to neglect the stop service.
(or)
try
{
//stop service code
}
catch(Exception e)
{
}
try this.

Stopping a foreground service on Android when the application crashes

I have an Android application where I implement a Service which interacts with some hardware over a Bluetooth serial connection. The setup of this connection is slow, so I decided to keep the service in the foreground, so if/when you want to view another application, the connection is ready to go (pseudocode follows):
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
start();
return (START_STICKY);
}
#Override
public void onDestroy() {
stop();
}
start() and stop() are private methods which start communication with the hardware, and in start's case, creates a Notification for use in startForeground() My Activity will call
#Override
public void onStart() {
super.onStart();
// Start the service
Intent intent = new Intent(getApplicationContext(), MyService.class);
ComponentName theService = startService(intent);
//this is to register the functions I need to handle functions my Activity calls
// to the service
bindService(intent, svcConn, BIND_AUTO_CREATE);
}
#Override
public void onStop() {
super.onStop();
if (theService != null) {
unbindService(svcConn);
theService = null;
if (isFinishing()) {
stopService(new Intent(getApplicationContext(), MyService.class));
}
}
}
I've had to add a "Quit" menu item to make sure that the Service shuts down. Worse, if my app crashes, I have to go in and manually kill the Service. Is there a way to elegantly kill the Service if things go horribly wrong, or am I abusing the purpose of a Service, and should find an alternative method of doing what I'd like to do?

Perhaps you can add a hook for your application's main thread(UI thread) for crash, see below:
Runtime.getRuntime().addShutdownHook(new Thread() {
public void run() {
//Kill the service.
}
});
throw new RuntimeException("Uncaught Exception");

Timeout in BroadcastReceivers using IntentServices

I've got two services running. They do their work and then reschedule themselves via the AlarmManager. In the BroadcastReceiver the only thing that happens is the launching of the service via Context.startService(). Both services are IntentServices, which as far as I can tell shouldn't be causing timeout problems. I've tried IntentServices, threading, and AsyncTasks but am repeatedly bumping up against the timeout error in the receivers themselves.
The timeout message is:
01-18 11:29:04.200: WARN/ActivityManager(73): Timeout of broadcast BroadcastRecord{433a4168 my.package.action.a} - receiver=android.os.BinderProxy#43399978
01-18 11:29:04.210: WARN/ActivityManager(73): Receiver during timeout: ResolveInfo{43394a30 my.package.MyReceiverA p=0 o=0 m=0x108000}
The basic structure of the two receivers:
public class MyReceiverA extends BroadcastReceiver {
public static final String ACTION_TO_BROADCAST = "my.package.action.a";
public void onReceive(Context context, Intent intent) {
// start the service
Intent serviceIntent = new Intent().setClassName(context,
MyServiceA.class.getName());
context.startService(serviceIntent);
}
}
And the services:
public class MyServiceA extends IntentService {
public ActivityMonitorService() {
super(TAG);
}
public IBinder onBind(Intent intent) {
// We don't allow anyone to bind to us
return null;
}
public void onCreate() {
super.onCreate();
_context = getApplicationContext();
_config = new Config();
if (_handler == null) {
_handler = new Handler();
}
}
/**
* Schedules an alarm to run ourselves again after ALARM_INTERVAL has passed.
*/
private void reschedule() {
Intent intent = new Intent(MyReceiverA.ACTION_TO_BROADCAST);
PendingIntent pendingIntent = PendingIntent.getBroadcast(_context, 0, intent, 0);
AlarmManager manager = (AlarmManager) _context.getSystemService(Context.ALARM_SERVICE);
manager.set(AlarmManager.RTC, now + delay, pendingIntent);
}
private void doWork() {
// Do some work. This could take a while. It also accesses a database that the two
// services share through synchronized blocks of code in static accessor functions.
}
protected void onHandleIntent(Intent intent) {
try {
doWork();
} catch (Exception e) {
// log it
} finally {
reschedule();
}
}
}

I figured out what was going on. Changing the two services to be a single one fixed the problem, meaning there was some sort of deadlock or race going on in the two. I'm assuming it's with their database access but haven't had a chance to verify it yet.
When changing to a single service the problem wasn't that the alarm was firing late, it's that the loaded down phone was pausing my service to give the music player the resources it needed. Looks like my options are to live with it or run the service in the foreground.