如何在iOS swift中对自定义FBSDK登录按钮进行操作

我收到的错误类似于“无法将类型为”（FBSDKLoginManagerLoginResult！，nError！）->Void）的值转换为预期的参数类型“FBSDKLoginManagerRequestTokenHandler！”。请帮我解决这个问题

func应用程序（application:UIApplication，openURL-url:NSURL，options:[String:AnyObject]）->Bool{return GIDSignIn.sharedInstance（）.handleURL（url，sourceApplication:options[uiapplicationopenurloptionsourceapplicationkey]as？字符串，注释：options[uiapplicationopenurloptionannotationkey]）func应用程序（应用程序：UIApplication，openURL url:NSURL，选项：[String:AnyObject]）->Bool{return GIDSignIn.sharedInstance（）.handleURL（url，sourceApplication:options[UIApplicationOpenUrlOptions SourceApplicationKey]as？字符串，注释：选项[UIApplicationOpenUrlOptions AnnotationKey]）

@IBAction func facebookLoginbuttonPressed(_ sender: FBSDKLoginButton) {

    let facebookLogin = FBSDKLoginManager()

    facebookLogin.logInWithReadPermissions(["email"],     fromViewController: self) { (facebookResult:     FBSDKLoginManagerLoginResult!, facebookError: NSError!) -> Void in
        print("Facebook login failed. Error \(facebookError)")
    } as! FBSDKLoginManager

}

@IBAction func selectFacebookLogin(sender: UIButton)
    {
        let fbLoginManager : FBSDKLoginManager = FBSDKLoginManager()

        fbLoginManager.logInWithReadPermissions(["public_profile", "email", "user_friends"], fromViewController: self)
        {
            (result, error) -> Void in
            if (error == nil)
            {
                let fbloginresult : FBSDKLoginManagerLoginResult = result
                if result.isCancelled
                {
                    return
                }

                if(fbloginresult.grantedPermissions.contains("email"))
                {
                    self.getFBUserData()
                }
            }
        }
    }

 func getFBUserData()
    {
        showIndicator()

        if((FBSDKAccessToken.currentAccessToken()) != nil)
        {
            FBSDKGraphRequest(graphPath: "me",
                                parameters: ["fields": "id, name, first_name, last_name, picture.type(large), email , gender"]).startWithCompletionHandler(
                                { (connection, result, error) -> Void in

                                    self.hideIndicator()

                if (error == nil)
                {
                   print(result)

                }
            })
        }
    }