The Drive Android API is a native API that conforms to standard Android best practices and coding conventions. It is an improvement over the generated client API, simplifying many common tasks associated with using the Drive service on mobile devices. The API automatically handles previously complex tasks such as offline access and syncing files. This allows you to read and write files as if Drive were a local file system.
The Drive Android API also significantly reduces the installed size of Drive-enabled apps. Because the API is part of the Google Play services client library, you no longer need to compile your app using the Google APIs Client Library for Java in order to access the Drive service.
Audience
This documentation assumes you are familiar with Android development and object-oriented programming concepts. You should also be familiar with Google Drive from a user's point of view.
API Overview
The Google Drive Android API provides abstractions for managing file content
and metadata. Files are represented by the
DriveFile interface;
folders by the DriveFolder interface.
Both share a common
superinterface, DriveResource, which
contains a DriveId. This is the
unique identifier for all files and folders.
The API also includes a package for querying for files based on metadata attributes, such as the title.
Resource metadata
Metadata for resources are encapsulated in the
Metadata class that contains
all details about a file or folder including the title, the MIME type, and
whether the file is editable, starred or trashed. The Metadata is fetched for a
DriveResource by calling the DriveResourceClient.getMetadata() method.
The Metadata may be set or changed when creating or updating a file using
a MetadataChangeSet and setting
the appropriate values, then calling the DriveResourceClient.updateMetadata()
method.
For more information, see Working with Metadata.
Files
You can open files programmatically using the
DriveResourceClient.openFile() method or by allowing the
user to select a file using a file selector activity created with the
DriveClient.newOpenFileActivityIntentSender() method.
The file contains a reference to the contents of the file, encapsulated in the
DriveContents class, which provides
access to read and write the underlying data. You can read the contents of a
drive file by accessing an input stream of its contents by calling
DriveContents.getInputStream().
To create a file, you can use either the
DriveResourceClient.createFile
method or the
DriveClient.newCreateFileActivityIntentSender()
method, which presents a dialog to the user that allows them to create the new
file in their Drive.
For more information about how to work with files, see Working with File Contents. For more information about how to create files, see Creating Files
Folders
The Drive for Android API has several methods for manipulating folders:
DriveResourceClient.createFolder(),DriveResourceClient.createFile(), methods for creating folders or files, respectively, within a folderDriveResourceClient.listChildren(),DriveResourceClient.queryChildren()methods for listing or querying the children of a folder.
For more information, see Working with Folders.
Activity Builders
The Drive for Android API has two methods that implement UI components to simplify common tasks associated with opening and creating files.
DriveClient.newCreateFileActivityIntentSender() method
helps you quickly create a file, set its initial folder, title, contents, and
metadata. The class also implements a simple UI that allows a user to specify
the file's title and destination folder. For more information, see
Creating Files.
DriveClient.newOpenFileActivityIntentSender() method
helps you easily open a file selected by the user.
The class displays a simple UI to let the user navigate and select from a list
of files that match the specified MIME types.
When you invoke the class, you specify an initial folder where the user's
navigation begins. You can also specify a preferred
set of MIME types for the file list.
Queries
Queries allow you to search for specific files or folders based on their
metadata attributes, such as the title. Queries are represented by the
Query class and can be constructed
using the Query.Builder class.
For more information, see Querying for Files.
Developer Resources
In addition to the sample code bundled with the Google Play services SDK, many more examples can be found at the official Google Drive GitHub repository.