Question

I’m very new to android. I would like to create a package that upon install would put files in the app folder (/data/data/my.app/…) of the android file system.

I would like to do this, so I could access the files using standard java File methods (in order to reuse my own code), and not have to use the android resource accessing methods.

The only way I thought might achieve something in this direction, is to put the files in the /res folder, and copy them to the file system in runtime (on first run, for example). This has the disadvantage of having two copies of each file for no reason.

Another way could be to get my app to download these files from a server (saw this option in another answer as well). This is possible, but I would wish to avoid having to put up a file server for such a simple task…

To my understanding, DDMS will not help here, as it only allows me to access the folder manually, after the application is installed.

My question is: Is there a different way to achieve my original goal (accessing files using standard java methods)? If not, is there a cleaner way to put files on the file system?

Thanks!

Answer 1

There are 3 methods I can think of that avoid duplication:

1. As you mentioned using the res/raw folder. You can avoid duplication if your existing code uses can use InputStream instead of File and use Resources.openRawResource().
2. Use the assets folder and access the file using file using AssetManager.openNotAssetFd(). Again this would require the use of Streams not File class. This can get a bit messy if your file is compressed because assets are memory mapped.
3. If you code is really tied to File (doesn’t just use it to open an InputStream). To avoid duplication you could download the file from the web on the first time it is run and store it into the external storage.