Resuming app causes the Players tab to not show its ListView

[hgzimmerman]

This used to be more generally caused by the activity restarting (ctrl+shift+r in Android Studio) as well as when the app was closed. The activity restart error was fixed by adding "setRetainInstance(true) inside of the player fragment. This prevents the app from GCing the fragment when the activity restarts. The fragment (or its activity) is still GCed when left alone long enough in the background (probably due to Marshmallow aggressively suspending apps to save battery). For a quick fix, I should find a way to restart the app when it detects itself resuming.

[hgzimmerman]

I seem to have fixed the problem by extending the FragmentStatePaerAdapter's saveState() method to return null, apparently preventing the app from doing something to the fragment when it tries to save.