You can do almost anything in Android. But one thing you can't do, it seems, is present users with a drop-down lost of something like a list of folders and enable them to either select one of these entries, or type in a new one which (in the case I'm interested in) would tell the app to create a new folder and add it to the drop-down list next time it's used. It's an interesting challenge to find a solution to this requirement. "Create a new class to extend Spinner", say the user forums. May have a go at that. If PCDB SuDoku Solver finishes up with a button tht s