Hmm, I think you want to show the background image in your open activity view. But you want to show this one from your gallery and it should be selected randomly from your gallery. If Iam right then you are in right place.
Getting the screen density programmatically in android
Some of the most programmers set alarm base background services are to schedule regular updates of application for offline data synchronization. In that case I think programmers should use the BroadcastReceiver for better results. There's no need to sched