类型“ ViewController”不符合协议“ FBSDKLoginButtonDelegate”

Question

I am trying to use Facebook API for the 1st time on an iOS App. I'm trying to implement a login button like told on facebook API doc.

Here is my app delegate :

import UIKit
import FBSDKCoreKit

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

    var window: UIWindow?


    func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
        // Override point for customization after application launch.
        //return true
        return FBSDKApplicationDelegate.sharedInstance().application(application, didFinishLaunchingWithOptions: launchOptions)
    }

    func application(application: UIApplication, openURL url: NSURL, sourceApplication: String?, annotation: AnyObject?) -> Bool
    {
        return FBSDKApplicationDelegate.sharedInstance().application(application, openURL: url, sourceApplication: sourceApplication, annotation: annotation)
    }

Here is my view controller:

    import UIKit
    import FBSDKCoreKit
    import FBSDKLoginKit

    class ViewController: UIViewController, FBSDKLoginButtonDelegate
    {


       // @IBOutlet weak var testLabel: UILabel!

        override func viewDidLoad() {
            super.viewDidLoad()

            if (FBSDKAccessToken.currentAccessToken() == nil)
            {
                NSLog("Not logged in..")
            }
            else
            {
                NSLog("Logged in..")
            }

            //Création et positionnement du bouton de login Facebook
            let loginButton:FBSDKLoginButton=FBSDKLoginButton()
            loginButton.center=self.view.center
            self.view.addSubview(loginButton)
            loginButton.delegate=self
            loginButton.readPermissions=["public_profile", "email", "user_fiends"]
            NSLog("UI OK")
        }

I am getting this error The type 'ViewController' does not conform to protocol 'FBSDKLoginButtonDelegate' on the line class ViewController: UIViewController, FBSDKLoginButtonDelegate

Whereas on a project that I found on the web using exactly the same syntax, no error comes up and the project builds without any problem.

Did anyone of you have the same problem ?

Answer 1

尝试实现FBSDKLoginButtonDelegate所需的方法。

Answer 2

in the new Xcode/iOS developing format is e if we use or declared any delegate's compulsory declare the method also, just like FBSDKLoginButtonDelegate we need to implement the delegate methods, else remove the delegate in Header

- (void)  loginButton:  (FBSDKLoginButton *)loginButton
didCompleteWithResult:  (FBSDKLoginManagerLoginResult *)result
                error:  (NSError *)error{

    NSLog(@"facebook login button test");


}