Looks like you are already doing it. onStart() you check if the intent is null and if it is, you create a new intent and bind it to a service (if it exists) otherwise create a new service.

Since onStart() is called every time your activity (not application) comes back from background to the foreground (say you launched the setting page and then come back to the main activity), it seems excessive to bind service during onStart(). I would move binding inside onCreate() since onCreate() is only called once for an activity.

Checking for null intent seems weird and maybe redundant, if you move binding inside onCreate(), you can be sure that you are only binding when the activity is launched, and if service already exists, activity will just bind to it.

I am working on an audio player app. The user may play the files, and a service is launched to allow them to play them in the background. I allow my service to continue playing the tracks even after the user chooses to swipe the app from the recent list.

Now, if the user swipes the app, the service will continue playing without issues but if the user opens the app using the notification associated with the service, I do not know how to handle this. To my surprise, the app actually continues working with the code above with no issues (as far as I can see).

Is there something I need to do to handle the said case? Do I need a way to reassign the service to the newly launched instance of my app?

Thanks.