Android Facebook和Google+离线登录

Question

My android application requires the user to login using Facebook or Google+ to see the contents of the app.

When the user is always connected to the internet everything works fine, i get the access token for the service he chose and life is good.

The thing is, i want the user to be able to auto-login without internet connection, using the last user he went online with. I have the last access token stored in a file, but i don't know what to do with it to make my app have that behaviour.

Answer 1

The access token you have stored in a file signifies two things:

1. The associated Android account was authenticated as a particular Google+/Facebook user ID.
2. The user has granted your app permission to make certain queries against Google+/Facebook APIs on their behalf.

The first part is valid regardless of whether you have an internet connection. As long as the associated Android account still exists on the device then you have an authenticated identity for the user. So you don't need to do anything specific with the access token, you can simply store the Android account that it is associated with and display the offline experience for that user.

The second part clearly won't work without an internet connection. So you will not be able to establish a connected PlusClient or Session object while the user has no internet connection.

Answer 2

You might notice that the user has no internet, and then not show the login activity. then if there's any info that you want to associate with what ever account they last logged in with, you will need your own data store to cache it in, so that you can sync it next time you notice they have internet.

See the similar question: https://stackoverflow.com/a/16538254/1449799