title: Long running Android 'service'
body: <p>I have an Android app, in which Activities fire long running operations that run in the background. These operations interact with the  Activities when done. I'm developing a component that handles the Activity/Long-Running-Task coupling, taking care of  activities being  destroyed and recreated.</p>
  
  <p>Right now that component is implemented as an Android service. The activities call bindService and use the resulting IBinder to start and track tasks. I decided against using startService, because I prefer the richer API possible through a Java interface.</p>
  
  <p>Now the problem. Activity A start ups, binds to the service and calls serviceApi.runTask(...). Activity A is then destroyed (because the user flips the phone, for instance) and recreated as Activity A'. A' then binds again to the service, announces its existence and everything should be running nicely.</p>
  
  <p>Except that my Service gets destroyed. When Activity A is destroyed, it unbinds from the service. Android sees there are no more clients, and  kills the service. When Activity A' is created, the service is created again, and I lose everything the  old service had.</p>
  
  <p>The only solution I can see is using a singleton for the service. And then it doesn't really have to be an Android service, just an instance that's accessible to everyone. Is that frowned upon in Android? Is there a better design that fits this problem?</p>
  
  <hr>
  
  <p>Editted: Even if I call startService and then bind to it, nothing guarantees that the service instance will exist as long as the application is running. Android can kill sticky services if resources are low. Killing the service will cause the application to malfunction, and I can't have that.</p>