To use the API, you first have to determine what kind of permission your app needs to access user’s media:
- read-only: allows media content to be read, but not modified
- read-write: allows media content to be read and modified
- add-files: allows media to be added to the galleries but prevents modifying existing media files.
To retrieve media content, use getMediaFilesystems(). If this is the first time your app is accessing the user’s media libraries, the system will prompt the user to grant access:
You can also make your app explicitly ask the user to designate specific galleries. This is useful if, for example, your app is only interested in pictures. Once access is granted, your app can then retrieve a list of LocalFileSystem structures. At that point, you can use the W3C FileSystem API to access the media gallery content.
NOTE: The file system APIs will only return files that the Chrome platform natively supports, and only the asynchronous version of the FileSystem API is currently supported.
We’re eager to see what great applications you will build with the Media Galleries API and the Chrome Packaged Apps platform. To get started, clone our samples repository and look at the Media Galleries sample application. Have questions or comments? Subscribe to chromium-apps and follow us on our Google+ page!