As3 Graph API Logout

问题:

i'm developing an application that'll be played by different's users, but i'm using the as3 graph api for authenticating users and posting on their wall, and i need to logout each user, before next user start his session on as3 graph api: http://code.google.com/p/facebook-actionscript-api/

I search to force FB to ask for login's info but after a logout when login again, API skip the step and log, on the last user session.

回答1:

This is an issue that's been continuously revised by FacebookMobile, Facebook, and FacebookDesktop. Basically, you'll need to make sure you set FacebookDesktop.manageSession = false; and pass in the 2nd argument of "logout" your site's api url. If that doesn't work, the other method is to use "reallyLogout", as detailed here in this thread.

The notes in comment #24 detail the way to expos the Access Token from FacebooMobile (or whichever singleton you're using), and then manually calling the logout.php method on Facebook, with the access token.

http://code.google.com/p/facebook-actionscript-api/issues/detail?id=297#c24

回答2:

None of the solutions I have seen on the web did work for me. The problem is indeed with StageWebView facebook cookie not being cleared on logout with FacebookMobile.logout() call. Loading logout.php with access token did not help me probably because there is no "next" parameter value for air applications that makes sense. I have seen people suggest to use localhost or facebook.com there but none of these options worked.

I have come up with a really questionable solution, but it works for now. The point is to logout user in facebook normally like he would logout on his own. To do this we need to load facebook.com in StageWebView and click logout. Logout button is a submit form item for "logout_form" html form. So we need to make a javaScript call

document.getElementById('logout_form').submit();

in our StageWebView. And we can do just that by calling

webView.loadURL("javascript:document.getElementById('logout_form').submit();");

in ActionScript.

The full code that I use for now

protected var _logoutAttemptInProgress:Boolean = false;
public function fbLogout():void{
if(!_isLoggedIn) return;
if(_logoutAttemptInProgress) return;
_logoutAttemptInProgress = true;

var webView:StageWebView = new StageWebView();
webView.viewPort = new Rectangle(-1, 0, 1, 1);          
webView.stage = this.stage;         
webView.loadURL("http://www.facebook.com/lksmlrsgnlskn");
webView.addEventListener(Event.COMPLETE, runLogoutJs);

function runLogoutJs(event:Event):void{
    webView.removeEventListener(Event.COMPLETE, runLogoutJs);
    var jsString:String = "document.getElementById('logout_form').submit();";
    webView.loadURL("javascript:"+jsString);
    webView.addEventListener(Event.COMPLETE, closeWebView);
}

function closeWebView(event:Event):void{
    webView.removeEventListener(Event.COMPLETE, closeWebView);
    webView.stage = null;
    webView.dispose();

    _isLoggedIn = false;
    _logoutAttemptInProgress = false;
}

FacebookDesktop.logout(null, APP_ORIGIN);
}

"lksmlrsgnlskn" is just some random garbage to get to error page that is much smaller than main page and loads faster.

FacebookDesktop.logout is to clear any local SharedObject data that Facebook lib might still have.

回答3:

This is a problem with the cookies, i mean, the firts user session remains and when you press to login the API logs in the first user.

I dont know why but the Facebook Api log out method dont log the user out of facebook, only log the user out from your application.

If you came to a solution or think something else, let me know so we could get the solution.