Question

I have a encrypted file, which on decryption is to opened in temporary memory, and when user closes the file they temporary file is deleted, What’s the way to achieve this functionality?

Answer 1

You cannot use external storage for the file since it will be available to whole world(what if user ejects SD card before you delete it?)

You should use internal storage so that you can remove it once the user is done. Use MODE_WORLD_READABLE so that user/other apps can only read it. When user is done, you can delete it.

String FILENAME = "hello_file";
String string = "hello world!";

FileOutputStream fos = openFileOutput(FILENAME, Context.MODE_WORLD_READABLE);
fos.write(string.getBytes());
fos.close();


File file = new File(FILENAME);
file.delete();