title: facebook $facebook->getSignedRequest(); error
body: <p>i am trying to add this script to my iframe app on facebook but it seems not to work:</p>
  
  <pre><code>    $signed_request = $facebook-&gt;getSignedRequest();
  $like_status = $signed_request["page"]["liked"];
  // If a fan is on your page
  if ($like_status) {
  echo 123;
  } else {
  // If a non-fan is on your page
  echo 456;
  }
  </code></pre>
  
  <p>i am placing the right app id and secret key and im calling facebook.php the right way. I get no errors or warnings, just that the script doesn't work.</p>
  
  <p><code>$like_status</code> doesn't return anything</p>
  
  <p>did the script changed? is there another version?
  thanks</p>
  
  <p>edit. more code:</p>
  
  <pre><code>&lt;?php
  require 'facebook.php';
  $app_id = "11549508592";
  $app_secret = "d898cb58b16f2aaaaaaaaaaaaaa";
  $facebook = new Facebook(array(
      'appId' =&gt; $app_id,
      'secret' =&gt; $app_secret,
      'cookie' =&gt; true
  ));
  $signed_request = $facebook-&gt;getSignedRequest();
  $like_status = $signed_request["page"]["liked"];
  echo "&lt;br&gt;like status = $like_status";
  ?&gt;
  </code></pre>