Android prevent users coping sqlite data

I'm developing an android app which provides a SQLite db. In that db different files might be stored (downloaded from somewhere). What I want to do, is to prevent users from coping those files. I mean, they can read the files within the app, but they must not be able to download the files, neither programmatically. So what is stored in the db, must absolutely be there and nowhere else.

I'm looking for a way to make SQLite password protected, or to encrypt my data. Can anyone suggest me some good practice please?

Thank you in advance!