checkLoginState for FB login api gives undefined in angular controller

Question

I am using the following code for Facebook login api :-

 function statusChangeCallback(response) {
    console.log('statusChangeCallback');
    console.log(response);
    if (response.status === 'connected') {
        testAPI();
    } else if (response.status === 'not_authorized') {
        document.getElementById('status').innerHTML = 'Please log ' +
            'into this app.';
    } else {
        document.getElementById('status').innerHTML = 'Please log ' +
            'into Facebook.';
    }
};

function checkLoginState() {
    FB.getLoginStatus(function(response) {
        statusChangeCallback(response);
    });
};

window.fbAsyncInit = function() {
    FB.init({
        appId      : '924067597708287',
        cookie     : true,

        xfbml      : true,
        version    : 'v2.5'
    });
    FB.getLoginStatus(function(response) {
        statusChangeCallback(response);
    });
};

(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/sdk.js";
    fjs.parentNode.insertBefore(js, fjs);
}(document, 'script', 'facebook-jssdk'));

function testAPI() {
    console.log('Welcome!  Fetching your information.... ');
    FB.api('/me', function(response) {
        console.log('Successful login for: ' + response.name);
        console.log('Successful login for: ' + response.id);
        console.log('Successful login for: ' + response.picture);
        document.getElementById('status').innerHTML =
            'Thanks for logging in, ' + response.name + '!';
        document.getElementById('pic').innerHTML =
            'Your user id is : ' + response.id + "<br />" +
            "<img src='" + "https://graph.facebook.com/" + response.id + "/picture?type=large' alt='' />";
    });
};

When I place the same code, within angular controller, I get an error message

checkLoginState is not defined

The login process stalls, but when I refresh, it shows logged in.

Please help.

Answer 1

Once you put checkLoginState into a controller, is it out of scope from FB (the sdk.js). So, define it on the window instead (you will need to inject $window).

    $window.checkLoginState = function() {
      FB.getLoginStatus(function(response) {
        console.log("checkLoginState: "+response);
      });
    }

You should then see this in the console after every click, which tells you that FB can reach the function:

checkLoginState: [object Object]