Representation of a document backed by either a
DocumentsProvider or a raw file on disk. This is a
utility class designed to emulate the traditional
File interface. It
offers a simplified view of a tree of documents, but it has substantial
overhead. For optimal performance and a richer feature set, use the
DocumentsContract methods and constants directly.
There are several differences between documents and traditional files:
- Documents express their display name and MIME type as separate fields, instead of relying on file extensions. Some documents providers may still choose to append extensions to their display names, but that's an implementation detail.
- A single document may appear as the child of multiple directories, so it doesn't inherently know who its parent is. That is, documents don't have a strong notion of path. You can easily traverse a tree of documents from parent to child, but not from child to parent.
- Each document has a unique identifier within that provider. This identifier is an opaque implementation detail of the provider, and as such it must not be parsed.
Before using this class, first consider if you really need access to an
entire subtree of documents. The principle of least privilege dictates that
you should only ask for access to documents you really need. If you only need
the user to pick a single file, use
Intent.ACTION_GET_CONTENT. If you want to let the user pick multiple
Intent.EXTRA_ALLOW_MULTIPLE. If you only need the user to
save a single file, use
Intent.ACTION_CREATE_DOCUMENT. If you use
these APIs, you can pass the resulting
fromSingleUri(Context, Uri) to work with that document.
If you really do need full access to an entire subtree of documents, start by
Intent.ACTION_OPEN_DOCUMENT_TREE to let the user pick a
directory. Then pass the resulting
fromTreeUri(Context, Uri) to start working with the user selected
As you navigate the tree of DocumentFile instances, you can always use
getUri() to obtain the Uri representing the underlying document for
that object, for use with
Indicates whether the current context is allowed to read from this file.
Indicates whether the current context is allowed to write to this file.
Create a new directory as a direct child of this directory.
Create a new document as a direct child of this directory.
Deletes this file.
Returns a boolean indicating whether this file can be found.