Android: Delete app associated files from external storage on Uninstall?

Question

It'd be convenient if an application I'm writing stored some files to external storage permanently (so they persist after the application has been exited[destroyed]), but on an uninstall I'd like to do the decent thing and have these files removed to free up the storage.

Is there any way I can have these files removed on an uninstall?

If there isn't (and I'm skeptical), then I'll have to create these files each time. I'm trying to save start-up time and also occupy required space by having them exist permanently.

Note: I need to use external storage, so both internal storage or a DB would be inappropriate.

Answer 1

Yes, this is possible. Simply write your files to the external files directory:

File dir = getExternalFilesDir(null);

This will create a folder at /Android/data/your.package/. Note that this is not External as in sdcard, but it is publicly accessible. If a user uninstalls your app, this directory will also be removed, along with all of its contents.

Answer 2

Quoting from the blog post of CommonsWare

• Internal storage: your file is deleted

• External storage: if you wrote your file to a location rooted at getExternalFilesDir() or getExternalCacheDir(), your file is deleted. If you wrote your file elsewhere (e.g., Environment.getExternalStoragePublicDirectory()), your file is not deleted

• Removable storage, prior to Android 4.4: removable storage is not officially accessible; if your file winds up out there, it should not be deleted when your app is uninstalled

• Removable storage, Android 4.4+: AFAIK, if you write to a supported location (getExternalFilesDirs() or getExternalCacheDirs()), your file is deleted if that particular bit of removable storage is in the device at the time of uninstall