Before we start: External storage means a real sd card or a connected mass storage USB device. This class can also be used to access the secondary storage (File.DirRootExternal). This becomes relevant with newer versions of Android that restrict direct access. It has nothing to do with runtime...
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2.This class can also be used to access the secondary storage (File.DirRootExternal). This becomes relevant with newer versions of Android that restrict direct access.
Storage Access Framework (SAF) is indeed one option that allows the user to grant access to directories and files. However, note that there are access restrictions to certain directories, such as the root and Android/data directories.