FBSDKLoginButton swift

viewcontroller FBSDKLoginButton.swift

// FBSDKLoginButtonDelegate has two required methods
//  loginButtonDidLogOut and loginButton(loginButton: FBSDKLoginButton!, didCompleteWithResult 

//
//  ViewController.swift
//
//  Created by Alan Jaw on 2/29/16.
//  Copyright © 2016 Alan Jaw. All rights reserved.
//

import UIKit
import FBSDKLoginKit
import Firebase

let ref = Firebase(url: "https://xxxxxxxx.firebaseio.com/")
let facebookLogin = FBSDKLoginManager()
let facebookPermissions = ["public_profile", "email", "user_friends"]

class ViewController: UIViewController, FBSDKLoginButtonDelegate {
    
    override func viewDidLoad() {
        super.viewDidLoad()

        
        // create facebook login button programmatically
        let loginButton = FBSDKLoginButton()
        loginButton.center = view.center
        
        loginButton.readPermissions = facebookPermissions
        loginButton.delegate = self
        view.addSubview(loginButton)
        
        
        if (FBSDKAccessToken.currentAccessToken() != nil)
        {
            // user logged in to facebook already
        }
        else {
            

        }
    }
    
    //MARK: FBSDKLoginButtonDelegate
    func loginButton(loginButton: FBSDKLoginButton!, didCompleteWithResult result: FBSDKLoginManagerLoginResult!, error: NSError!) {
        if ((error) != nil) {
            // Process error
        }
        else if result.isCancelled {
            // Handle cancellations
        }
        else {
            // Navigate to other view
            print ("facebook login complete")
        }
    }
    
    func loginButtonDidLogOut(loginButton: FBSDKLoginButton!) {
        print ("logged out of facebook")
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }


}

Thanks for good code!

ditto, thanks