AdWhirl implementation in iPhone Cocoa touch

i'm starting to implement AdWhirl in my application. i follow the instructions which is belong to adwhirl but i cant see any ad in my application.i add the following methods in my viewcontroller class

- (void)viewDidLoad {
    [super viewDidLoad];
 AdWhirlView *adView=[AdWhirlView requestAdWhirlViewWithDelegate:self];
 [self.view addSubview:adView];
}

-(NSString *) adWhirlApplicationKey{
 return @"myAdWhirlKey";
}

-(UIViewController *) viewControllerForPresentingMod开发者_JAVA技巧alView{
 return self;
}

i doesn't display anything. please help how to implement AdWhirl

you need to see AdWhirl tutorial and you can download it from here Tutorial

You need to pass the AdWhirl SDK key in adWhirlApplicationKey delegate to work. check the link to get adWhirlkey... http://chandanshetty01.blogspot.com/2011/06/integrating-ads-to-ios-apps-using.html