i have troubles with my STICKY Service. I call it in my MainActivity.class and bind it:
MainActivity:
Intent intent = new Intent(this, MyService.class);
ComponentName MyCompName= startService(intent);
bindService(intent, MyConnection, Context.BIND_AUTO_CREATE);
and...
MyService
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
super.onStartCommand(intent, flags, startId);
return START_STICKY;
}
I want that this Service runs STICKY and never be closed or restarted. But when i close my Application, the onCreate()-Method of MyService is called and all variables are reseted, and i don´t know why.
BTW: I don´t call stopService!
The difference between STICKY and NON_STICKY services is that STICKY services are restarted after being killed. I don't think it's possible to guarantee that your service will never be restarted - if memory is low it might be restarted.
If you need to preserve the state, you can save variables in a database. To see if the service is being created for the first time or restarted, you can check if the intent in onStartCommand is null.
If you only need to preserve the initial state when the service was created, you can use START_REDELIVER_INTENT which will resend the Intent used to create the service in onStartCommand.
Related
I have a service start in Activity A with
private void startService() {
Intent pushIntent = new Intent(this, MyService.class);
pushIntent.putExtra(MyService.TYPE_SCREEN, 1);
startService(pushIntent);
}
in my Service I get data from onStartCommand
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
typeScreen = intent.getExtras().getInt(TYPE_SCREEN);
return Service.START_STICKY;
}
I want when change from activity A to activity B, I will update type of screen from 1 to 2 in Service.
How I can do it?
Android only create one instance of a service.
Request that a given application service be started. The Intent can
either contain the complete class name of a specific service
implementation to start, or an abstract definition through the action
and other fields of the kind of service to start. If this service is
not already running, it will be instantiated and started (creating a
process for it if needed); if it is running then it remains running.
So in your case, the service is already running, then you just have to send the intent with the screen 2 extra. It will only call the onStartCommand Override method.
Intent pushIntent = new Intent(this, MyService.class);
pushIntent.putExtra(MyService.TYPE_SCREEN, 2);
startService(pushIntent);
public int onStartCommand(Intent intent, int flags, int startId) {
}
When a service is started, I pass an intent to startService function. When service is restarted by the OS due to Sticky flag, is that very same intent that I passed to it to start the service be passed to onStartCommand again or will it be null?
Intent is only passed again if you request START_REDELIVER_INTENT
What is START_STICKY,START_NOT_STICKY and START_REDELIVER_INTENT Service
The below service is triggered via button click from some other app (by firing pending Intent). The onStartCommand() creates a Messages and dispatches using send() method. Ideally, I expect onStartCommand to be called everytime button is clicked, as a pending intent is used to fire the service on buttonClick.
But onstartCommand() is called only once, for the first time the button is clicked. Subsequent button clicks do not trigger the onStartCommand().
Interestingly if I comment the line
replyTo.send(msg);
onStartCommand gets called each time the button from other app is clicked.
Therefore dispatching the Message using android IPC Messenger from within the service might be causing the issue. I confirmed the Message reaches the destination app successfully. Am I missing some detail about Messages , like blocking send call?
I am returning 'START_STICKY' from onStartCommand(), that also might be the reason.
Any insights on what is happening will be welcome.
//MyService.java
#Override
public void onCreate() {
// create RemoteViews -> rView
Intent intent = new Intent(getBaseContext(), MyService.class);
PendingIntent pendingIntent = PendingIntent.getService(getBaseContext(), 0, intent, 0);
rView.setOnClickPendingIntent(buttonId, pendingIntent);
//On click of the above button, this MyService will be started usingthe given pendingintent
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.e("debug","Service onStartCommand");
Message msg = Message.obtain(null, UPDATE_REMOTE_VIEW, rView);
try {
replyTo.send(msg);
} catch (RemoteException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return START_STICKY;
}
Bonus Detail: The pendingIntent on the Button (from other app) is set using setOnclickPendingIntent() (RemoteViews class).
What I did in my similar case is to implement onStartCommand as follow:
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
//
// ... HERE support for intent sent by setOnClickPendingIntent ...
//
return super.onStartCommand(intent, flags, startId);
}
And it seems to work. onStartCommand is called multiple times (as many as the number of click on my RemoteViews).
From Docs:
Clients can also use Context.bindService() to obtain a persistent
connection to a service. This likewise creates the service if it is
not already running (calling onCreate() while doing so), but does not
call onStartCommand(). The client will receive the IBinder object that
the service returns from its onBind(Intent) method, allowing the
client to then make calls back to the service. The service will remain
running as long as the connection is established (whether or not the
client retains a reference on the service's IBinder). Usually the
IBinder returned is for a complex interface that has been written in
aidl.
So, it may be because of the use of bindService
I have an android app with service that has to track user's location even with closed application only if user set flag in app. So I start service in code after user clicks button and stop when he clicks it again with following code
alarm.changeAlarmStatus();
if(alarm.getAlarmStatus()) {
SharedPreferences.Editor ed = alarmPreferences.edit();
ed.putFloat("MARKER_LATITUDE", (float) theMarker.getPosition().latitude);
ed.putFloat("MARKER_LONGITUDE", (float) theMarker.getPosition().longitude);
ed.commit();
startService(myIntent);
}
else{
stopService(myIntent);
}
It seems to work fine. Service works and does what it should. But problem is if I close application through the task manager I see in logcat that Service starts again(but only if service is already working) and it causes nullPointerException because intent is null. You can see in this code why it happens
public int onStartCommand(Intent intent, int flags, int startId) {
super.onStartCommand(intent, flags, startId);
Bundle bundle = intent.getExtras();
alarm = (Alarm) bundle.getSerializable("alarm");
Log.d("service","On Start Command is called ");
serviceIntent = intent;
return START_STICKY;
}
However I need to start my service only by pressing button and no other way. Does anyone know how to fix that?
Return START_NOT_STICKY in onStartCommand instead of START_STICKY.
If START_STICKY is returned, system will try to re-create service after it is killed.
If START_NOT_STICKY is returned, system will not try to re-create service after it is killed.
I'm trying to do a StartedService in android to send periodically the user location to a server.
Until this moment I managed to create the service and starting it from the 'parent ' application and I don't know how to keep it alive after the application was killed. From what I found on internet the 'StartCommandResult.Sticky' should restart the service if this one is killed but from some reason this is not restarted.
I overried the OnStartCommand:
public override StartCommandResult OnStartCommand(Intent intent, StartCommandFlags flags, int startId)
{
locationTask = new Task(() =>
{
//stuff to do
});
locationTask.Start();
return StartCommandResult.Sticky;
}
And the service is started like this:
Intent intent = new Intent(this.Activity, Class.FromType(typeof(LocationService)));
this.Activity.StartService(intent);
Any suggestions what should I do in order to keep my service alive after the application was killed?
As observation I'm using xamarin to do it, but I won't mind an answer in android(java).
As stated in the official documentation:
A service is "started" when an application component (such as an
activity) starts it by calling startService(). Once started, a service
can run in the background indefinitely, even if the component that
started it is destroyed. Usually, a started service performs a
single operation and does not return a result to the caller. For
example, it might download or upload a file over the network. When the
operation is done, the service should stop itself.
So, starting the service like this
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
return Service.START_STICKY;
}
Will have your service running even while your app is destroyed.
Regarding Service.START_STICKY in the official documentation:
If the system kills the service after onStartCommand() returns,
recreate the service and call onStartCommand(), but do not redeliver
the last intent. Instead, the system calls onStartCommand() with a
null intent, unless there were pending intents to start the service,
in which case, those intents are delivered. This is suitable for media
players (or similar services) that are not executing commands, but
running indefinitely and waiting for a job.
This is how I do it but its in JAVA code.
in your service you should implement a LocalBinder, onStartCommand and onCreate methods.
public class LocalBinder extends Binder {
ServiceName getService() {
return ServiceName .this;
}
}
#Override
public void onCreate() {
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.i("LocalService", "Received start id " + startId + ": " + intent);
return START_STICKY;
}
The onStartCommand should return START_STICKY;. And also, include this code on your Service:
#Override
public void onTaskRemoved(Intent rootIntent) {
// TODO Auto-generated method stub
Intent restartService = new Intent(getApplicationContext(),this.getClass());
restartService.setPackage(getPackageName());
PendingIntent restartServicePI = PendingIntent.getService(getApplicationContext(), 1, restartService, PendingIntent.FLAG_ONE_SHOT);
AlarmManager alarmService = (AlarmManager)getApplicationContext().getSystemService(Context.ALARM_SERVICE);
alarmService.set(AlarmManager.ELAPSED_REALTIME, SystemClock.elapsedRealtime() +1000, restartServicePI);
}
This will restart your Service on 1 second from the time you close it. Also, dont forget to add your service in your AndroidManifest.xml
<service android:name=".ServiceName"
android:exported="false"
android:stopWithTask="false" >
</service>
Override onStartCommand like this
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
return Service.START_STICKY;
}
For me, everything in the code was right but the problem was with the use of debugging while checking if the service was on. When I use a release version (or just dev version without connecting to the debug), the process is not killed and the service is running normally.
No idea why though. I am using Xamarin Studio 6.0.