Can I run Android GeoFencing entirely within a background service?

Question

I have an app which needs almost no user interaction, but requires Geofences. Can I run this entirely within a background service?

There will be an Activity when the service is first run. This Activity will start a service and register a BroadcastReceiver for BOOT_COMPLETED, so the service will start at boot. It's unlikely that this Activity will ever be run again.

The service will set an Alarm to go off periodically, which will cause an IntentService to download a list of locations from the network. This IntentService will then set up Geofences around those locations, and create PendingIntents which will fire when the locations are approached. In turn, those PendingIntents will cause another IntentService to take some action.

All this needs to happen in the background, with no user interaction apart from starting the Activity for the first time after installation. Hence, the Activity will not interact with LocationClient or any location services.

I've actually got this set up with proximityAlerts, but wish to move to the new Geofencing API for battery life reasons. However, I have heard that there can be a few problems with using LocationClient from within a service. Specifically, what I've heard (sorry, no references, just hearsay claims):

• location client relies on ui availability for error handling
• when called from background thread, LocationClient.connect() assumes that it is called from main ui thread (or other thread with event looper), so connection callback is never called, if we call this method from service running in background thread

When I've investigated, I can't see any reason why this would be the case, or why it would stop my doing what I want. I was hoping it would be almost a drop-in replacement for proximityAlerts...

Can anyone shed some light on things here?

Sphygmoid

Answer 1

The best thing would be to just try it out, right? Your strategy seems sound.

when called from background thread, LocationClient.connect() assumes that it is called from main ui thread (or other thread with event looper), so connection callback is never called, if we call this method from service running in background thread.

I know this to be not true. I have a Service that is started from an Activity, and the connection callback is called.

I dont know about proximity alerts; but I cant seem to find an API to list my GeoFences. I am worried that my database (sqlite) and the actual fences might get out of sync. That is a design flaw in my opinion.

The reason LocationClient needs UI, is that the device may not have Google Play Services installed. Google has deviced a cunning and complex mechanism that allows your app to prompt the user to download it. The whole thing is horrible and awful in my opinion. Its all "what-if what-if" programming.

(They rushed a lot of stuff out the door for google IO 2013. Not all of it are well documented, and some of it seems a bit "rough around the edges").

Gilligan

I couldn't find and API to list Geofences either, and I would love to have one as well. I'm also worried that my sqlite db and the actual list of registered fences is out of sync... – Outstrip