I'm working on books library in my android app... so I want to add a functionality that allows the user to view the books that he/she has downloaded by my app..
any idea or hint to work this out?
The final solution depends a bit on the details you want to store for the books. If you only want to store the book title and author and you don't want to deal with a database yet then SharedPreferences might be an option. But they are more like Java Properties files and with this said not a good solution for persisting more complex data structures.
If you want to store more metadata of the books (e.g. the current read position, bookmarks, etc.) then you will need a database sooner or later. I recommend thinking about the data model first and then start with the SQLite database included in Android.
You can find more details here Android Developers - Data Storage
One of the way to keep track is whenever a book is downloaded store the required data in database and retrive it whenever required or delete it from database if no required in future.
Try this way.
If your app has already downloaded books, then you need a ListView to display them.
If, however, the problem is both in saving and listing, you should read the dev guide, esp about using File and getExternalFileDir.
来源：https://stackoverflow.com/questions/9953537/how-to-list-my-app-downloads