FB.getLoginStatus always returns null regardless if user is logged into FB

I'm trying to see if a user is logged into FB on my website. I have the following code below but regardless if I'm logged into my FB account or not the FB.getLoginStatus response is always returning null.

<script type="text/javascript">
window.fbAsyncInit = function() {
FB.init({appId: 'XXXXXXXXXXXXXXX', status: true, cookie: true,
         xfbml: true});
FB.getLoginStatus(function(response) {
  if (response.session) {
    alert('Logged In');开发者_开发知识库
  } else {
    alert('Not Logged In');
  }
});
};

(function() {
var e = document.createElement('script'); e.async = true;
e.src = document.location.protocol +
  '//connect.facebook.net/en_US/all.js';
document.getElementById('fb-root').appendChild(e);
}());
</script>

So it turns out this was a misinterpretation of the FB docs. The session will only return if the user is connected to the app. To see if the user is logged in but not connected you need to use response.status

maybe response.session is deprecated, official working example from Facebook: To determine if a user is connected to your app:

FB.getLoginStatus(function(response) {
  if (response.authResponse) {
    // logged in and connected user, someone you know
  } else {
    // no user session available, someone you dont know
  }
});