Facebook login button not redirecting - facebook

Question

I can't seem to understand why I'm not being redirected to the appropriate page. It certainly exists. Instead of redirecting me, a screen pops up and just goes away after a second.
<div id='fb-root'></div>
<script>
window.fbAsyncInit = function()
{
FB.init({
appId: 'ID',
status: true,
cookie: true,
xfbml: true
});
FB.Event.subscribe('auth.login', function(response)
{
window.location = '/fb_redirect.php';
});
};
(function(d, s, id) {
var js, fjs = d.getElementsByTagName(s)[0];
if (d.getElementById(id)) return;
js = d.createElement(s); js.id = id;
js.src = '//connect.facebook.net/en_US/all.js#xfbml=1&appId=ID';
fjs.parentNode.insertBefore(js, fjs);
}(document, 'script', 'facebook-jssdk'));
</script>
<div class='fb-login-button' data-show-faces='false' scope='email' data-width='200' data-max-rows='1'></div>

Answer 1

Instead of doing FB.Event.subscriber, try the following:
FB.getLoginStatus(function(response) {
if (response.status === 'connected') {
if ( typeof response != 'undefined' && typeof response.authResponse != 'undefined' ) {
window.location = '/fb_redirect.php';
}
} else if (response.status === 'not_authorized') {
// the user is logged in to Facebook,
// but has not authenticated your app
} else {
// the user isn't logged in to Facebook.
}
});
The function will return connected if the user is logged in, and it will then redirect them to any page your want. You can keep the FB.Event.subscriber function in there for users who need to login for the first time, and the above code will work for returning users.