Facebook login Xcode nothing happen

Hello everyone ,

i just started to use xcode for ios app programming so im pretty bad using it. I tried to just add a Facebook login button into my first app .It is loading it but when i click on it nothing happen. I followed this tutorial : https://developers.facebook.com/docs/facebook-login/ios/v2.4

This is my code :

//AppDelegate.h

 #import <UIKit/UIKit.h>
 #import <FBSDKCoreKit/FBSDKCoreKit.h> 
#import <FBSDKCoreKit/FBSDKCoreKit.h>
 #import <FBSDKLoginKit/FBSDKLoginKit.h> 
@interface AppDelegate : UIResponder <UIApplicationDelegate> 
@property (strong, nonatomic) UIWindow *window;
@end

//Appdelegate.m
#import "AppDelegate.h"
#import <FBSDKCoreKit/FBSDKCoreKit.h>
#import <FBSDKLoginKit/FBSDKLoginKit.h>
@interface AppDelegate ()
@end
@implementation AppDelegate
- (void)applicationDidBecomeActive:(UIApplication *)application {
    [FBSDKAppEvents activateApp];
}
- (BOOL)application:(UIApplication *)application
didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    /
    [FBSDKLoginButton class];

    return YES;
}
- (BOOL)application:(UIApplication *)application
            openURL:(NSURL *)url
  sourceApplication:(NSString *)sourceApplication
         annotation:(id)annotation {
    return [[FBSDKApplicationDelegate sharedInstance] application:application
                                                          openURL:url
                                                sourceApplication:sourceApplication
                                                       annotation:annotation];
}
- (void)applicationWillResignActive:(UIApplication *)application {
    /
    /
}
- (void)applicationDidEnterBackground:(UIApplication *)application {
    /
    /
}
- (void)applicationWillEnterForeground:(UIApplication *)application {
    /
}
- (void)applicationWillTerminate:(UIApplication *)application {
    /
}
@end

//ViewController.h

#import <UIKit/UIKit.h>
#import <FBSDKCoreKit/FBSDKCoreKit.h>
#import <FBSDKLoginKit/FBSDKLoginKit.h>
@interface ViewController : UIViewController
@end

//ViewController.m
#import "ViewController.h"
#import <FBSDKCoreKit/FBSDKCoreKit.h>
#import <FBSDKLoginKit/FBSDKLoginKit.h>
@interface ViewController ()
@end
@implementation ViewController
- (void)viewDidLoad {
    [super viewDidLoad];
    FBSDKLoginButton *loginButton = [[FBSDKLoginButton alloc] init];
    loginButton.center = self.view.center;
    [self.view addSubview:loginButton];
    /
}
- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    /
}
@end

Any help would be more than appreciate.

Cheers guys