butterfly viewcontroller 2

    class ViewController: UIPageViewController, UIPageViewControllerDataSource, PFLogInViewControllerDelegate, PFSignUpViewControllerDelegate {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
    }
    
    override func viewDidAppear(animated: Bool) {
        
        super.viewDidAppear(animated)
        if (PFUser.currentUser() == nil) {
            let loginViewController = LoginViewController()
            /// TODO: THIS IS NOT WORKING. LOGIN BUTTON NOT SHOWING, POSSIBLE BUG
            loginViewController.fields = [PFLogInFields.Facebook]
            loginViewController.delegate = self
            loginViewController.emailAsUsername = false

            loginViewController.facebookPermissions = ["public_profile", "email", "user_friends", "user_education_history", "user_birthday"]
            loginViewController.signUpController?.delegate = self

            self.presentViewController(loginViewController, animated: false, completion: nil)

        }