สอบถามเรื่อง facebook SDK v. 4.0.1 ครับ ผมใช้แล้วเชื่อมต่อไม่ได้

use Facebook\FacebookSession;
use Facebook\FacebookRequest;
use Facebook\GraphUser;
use Facebook\FacebookRequestException;

FacebookSession::setDefaultApplication('YOUR_APP_ID','YOUR_APP_SECRET');

// Use one of the helper classes to get a FacebookSession object.
//   FacebookRedirectLoginHelper
//   FacebookCanvasLoginHelper
//   FacebookJavaScriptLoginHelper
// or create a FacebookSession with a valid access token:
$session = new FacebookSession('access-token-here');

// Get the GraphUser object for the current user:

try {
  $me = (new FacebookRequest(
    $session, 'GET', '/me'
  ))->execute()->getGraphObject(GraphUser::className());
  echo $me->getName();
} catch (FacebookRequestException $e) {
  // The Graph API returned an error
} catch (\Exception $e) {
  // Some other error occurred
}