Facebook Like Gate like_status is empty - php

Question

so basically im trying to get a like gate working but the $like_status variable never changes so my condition to change to the liked content will never work. Does anyone know why this never changes? Have added my app to a page tab on facebook and it gets all the other variables $page_id, $page_admin, $country and $locale but not $like_status.
Thanks Charlie
See Code Below
<?php
enter code here
require_once('AppInfo.php');
// Enforce https on production
if (substr(AppInfo::getUrl(), 0, 8) != 'https://' && $_SERVER['REMOTE_ADDR'] != '127.0.0.1') {
header('Location: https://'. $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI']);
exit();
}
// This provides access to helper functions defined in 'utils.php'
require_once('utils.php');
require 'includes/facebook.php';
// Create our Application instance.
$facebook = new Facebook(array(
'appId' => AppInfo::appID(),
'secret' => AppInfo::appSecret(),
'cookie' => true
));
$signed_request = $facebook->getSignedRequest();
$page_id = $signed_request["page"]["id"];
$page_admin = $signed_request["page"]["admin"];
$like_status = $signed_request["page"]["liked"];
$country = $signed_request["user"]["country"];
$locale = $signed_request["user"]["locale"];
echo "<br>page id = $page_id";
echo "<br>page admin = $page_admin";
echo "<br>like status = $like_status";
echo "<br>country = $country";
echo "<br>locale = $locale";
function grokSignedRequest()
{
if (isset($_REQUEST['signed_request']))
{
$encoded_sig = null;
$payload = null;
list($encoded_sig, $payload) = explode('.', $_REQUEST['signed_request'], 2);
$sig = base64_decode(strtr($encoded_sig, '-_', '+/'));
$data = json_decode(base64_decode(strtr($payload, '-_', '+/'), true));
return $data;
}
return false;
}
// call the function to parse the signed request
$sr_data = grokSignedRequest();
// check like status
if ($sr_data->page->liked==1)
{
include ('includes/index2.php');
}
else
{
include ('includes/index1.php');
}
?>

Answer 1

If you are running your PHP code on a tab page, like_status is probably actually present, but set to a value of 0 (zero). Thus, the echo statement seems to be outputting nothing for $like_status, but in reality, it has a value of zero. To prove this try code like this:
if ($like_status == 0)
echo "it's zero";
else
echo "it's not zero";

Answer 2

Edit: Sorry, I didn´t see that #robbie solved this in the comments of the question
The user must arrive to the App from the page tab, and:
As with a Canvas Page, you will not receive all the user information accessible to your app in the signed_request until the user authorizes your app.
https://developers.facebook.com/docs/appsonfacebook/pagetabs/#integrating