BeaconManager#unbind throws IllegalArgumentException

[hborders]

Sometimes, Beaconmanager#unbind throws an IllegalArgumentException:

Caused by: java.lang.IllegalArgumentException: Service not registered: org.altbeacon.beacon.BeaconManager$1@b639ead
1   android.app.LoadedApk.forgetServiceDispatcher   LoadedApk.java, line 1029
2   android.app.ContextImpl.unbindService   ContextImpl.java, line 1808
3   android.content.ContextWrapper.unbindService    ContextWrapper.java, line 551
4   com.example.BeaconUtils$BeaconConsumerImpl.unbindService    BeaconUtils.java, line 195
5   org.altbeacon.beacon.BeaconManager.unbind

I'm calling BeaconManager#bind and BeaconManager#unbind synchronously in a background thread. I wait for BeaconConsumer#onBeaconServiceConnect or a timeout, then I wait for MonitorNotifier#didDetermineStateForRegion or a timeout, I call BeaconManager#unbind. Occasionally, BeaconManager#unbind fails. Based on my review of your source. Two things could cause this:

BeaconManager#bind's call to BeaconConsumer#bindService could fail. BeaconManager#bind doesn't return this success boolean to the caller, nor does it handle this failure in any way internally. If we later call BeaconManager#unbind, the call will throw the IllegalArgumentException described above.

BeaconManager#beaconServiceConnection could receive an #onServiceDisconnected callback after BeaconManager#bind is called. Since BeaconManager#beaconServiceConnection is already unbound, when we later call BeaconManager#unbind, the call will throw the IllegalArgumentException described above.

Please make BeaconManager#bind return a success boolean, and add a onBeaconServiceDisconnect method to BeaconConsumer.

Thanks!

[davidgyoung]

Thanks for the feedback, these are good suggestions.

I imagine you can catch the exception in unbind for now, but I agree that this needs to be fixed.

[X4mp]

I run in the same problem. I use a custom BeaconScanner class which implements BeaconConsumer and I implement all the methods. For bindService and unbindService i forward the call to mContext#bindService(intent, serviceConnection, flags). When I call BeaconManager.unbind() the IllegalArgumentException is thrown.

Is there any fix for this right now? If not, do you have any suggestions on how to use BeaconConsumer in a custom class?

Edit:
I guess the problem was that I tried to reinitialise the BeaconManager for every Activity which I register as a Listener to the beacon events. Because I don't really understand how beaconManager#bind(this) and beaconManager#unbind(this) work, I solved the problem by just calling initializeBeaconManager(), which calls beaconManager#bind(), just when my first Activity is registered. Every following Activity is just registered as a listener, but don't calls initializeBeaconManager() anymore.

[vinceramcesoliveros]

just want to say Hi because I get an error to a different platform, although it is somewhat related. I'm using Flutter project, I created an issue to the guy created the package using altbeacons. then i get this error.

Edit: kinda fixed the issue now by commenting beaconClient.unbind().

[darshithedpara]

@Ram231 Could you share your code snippet I am facing same issue in my flutter project.

[vinceramcesoliveros]

@Ram231 Could you share your code snippet I am facing same issue in my flutter project.

@darshithedpara . The project is dead(flutter beacons). I think you should find another alternatives like a flutter BLE. My project is now in graveyard and can't update the packages anymore.

[davidgyoung]

A few tips:

1. The best way around this problem for now is to reduce the frequency in which you call bind/unbind. Don't do it every time a screen appears or disappears or you increase the risk of unbind failures.

2. You can catch the exception in unbind as a fail safe.

3. Anyone who wants to work on a pull request for an internal fix is encouraged to do so. API changes must be backward compatible and cause minimal changes.

[davidgyoung]

closed per #1046