Login Google with Android and App Engine (GAE)

Question

I have a project on Google App Engine and an Android project. I need to do login on GAE using Android.

On GAE, I have this code: (redirect user to google login page, it's exactly I want!)

    UserService userService = UserServiceFactory.getUserService();        
    String URL = request.getRequestURI();

    if (request.getUserPrincipal() != null) {
        // I need to send the MY_GENERATED_TOKEN to my android app
        response.getWriter().println(MY_GENERATED_TOKEN);
    } else {
        response.sendRedirect(userService.createLoginURL(URL));
    }

This code is default, and suggested by Google. My problem is that I don't know how access this on my Android app.

I have an Android activity, with a button. I want that when I click on button, open the android browser on Google's login page, I do login, the browser closes automatically and my app receives the token generated by GAE (it isn't a google token, it is a token generated by me).

I don't want to use endpoints.

Answer 1

If you really want to open it with the default browser here is my approach:

1. Open Login Page url
2. Login then redirect to an android handled intent-filter from your app
    # example: http://your-caught-login-intent-filter.example.com or
    # your-app-login://scheme
3. Pass along the token and you're set

But I suggest just use the webview, then you'll have more control:

1. Create a webview, then load the login url
2. Make sure to set the webviewClient onFinishPage
3. Lookup the resulting html for your token

http://developer.android.com/reference/android/webkit/WebView.html