Navigation pushview Controller is not working
===

I am implement the TabBar app for ipad & iphone both. But In IPAD the navigation controller is not working for ipad nib in table cell. The viewdid Load method is not call for ipad.
But it work fine for iphone..
Help me!!

my didfinishLaunch method is as follow:
 

    if ([self isPad]) {
            UINavigationController *nc1;
            nc1 = [[UINavigationController alloc] init];
            [nc1.navigationBar setTintColor:[UIColor blackColor]];
            
    
            UIViewController *viewController1 = [[[FirstScreen alloc] initWithNibName:@"FirstScreen_ipad" bundle:nil] autorelease];
            nc1.viewControllers = [NSArray arrayWithObjects:viewController1, nil];
            
            UINavigationController *nc2;
            nc2 = [[UINavigationController alloc] init];
            [nc2.navigationBar setTintColor:[UIColor blackColor]];
            UIViewController *viewController2 = [[[FullList alloc] initWithNibName:@"FullList_ipad" bundle:nil] autorelease];;
            nc2.viewControllers = [NSArray arrayWithObjects:viewController2, nil];
    //        
            
            UIViewController *viewController3 = [[[FavouriteView alloc] initWithNibName:@"FavouriteView_ipad" bundle:nil] autorelease];
            
            UIViewController *viewController4 = [[[UpcomingFights alloc] initWithNibName:@"UpcomingFights_ipad" bundle:nil] autorelease];
            UIViewController *viewController6 = [[[ConnectView alloc] initWithNibName:@"ConnectView_ipad" bundle:nil] autorelease];
            
            
            UIViewController *viewController7 = [[[MediaView alloc] initWithNibName:@"MediaView_ipad" bundle:nil] autorelease];
            
    
            
            self.tabBarController = [[[UITabBarController alloc] init] autorelease];
            self.tabBarController.viewControllers = [NSArray arrayWithObjects:nc1,nc2,viewController3,viewController4 ,viewController6 ,viewController7 ,nil];
            
           
        }
        else
        {
    
            UINavigationController *nc1;
            nc1 = [[UINavigationController alloc] init];
            [nc1.navigationBar setTintColor:[UIColor blackColor]];
            
    
        UIViewController *viewController1 = [[[FirstScreen alloc] initWithNibName:@"FirstScreen" bundle:nil] autorelease];
        nc1.viewControllers = [NSArray arrayWithObjects:viewController1, nil];
        
       UINavigationController *nc2;
       nc2 = [[UINavigationController alloc] init];
       [nc2.navigationBar setTintColor:[UIColor blackColor]];
       UIViewController *viewController2 = [[[FullList alloc] initWithNibName:@"FullList" bundle:nil] autorelease];;
       nc2.viewControllers = [NSArray arrayWithObjects:viewController2, nil];
    
        
        UIViewController *viewController3 = [[[FavouriteView alloc] initWithNibName:@"FavouriteView" bundle:nil] autorelease];
        UIViewController *viewController4 = [[[UpcomingFights alloc] initWithNibName:@"UpcomingFights" bundle:nil] autorelease];
        UIViewController *viewController6 = [[[ConnectView alloc] initWithNibName:@"ConnectView" bundle:nil] autorelease];
        
        
        UIViewController *viewController7 = [[[MediaView alloc] initWithNibName:@"MediaView" bundle:nil] autorelease];
            
          
        self.tabBarController = [[[UITabBarController alloc] init] autorelease];
        self.tabBarController.viewControllers = [NSArray arrayWithObjects:nc1, nc2,viewController3,viewController4 ,viewController6 ,viewController7 ,nil];
            
             }
        self.window.rootViewController = self.tabBarController;
        [self.window makeKeyAndVisible];
        return YES;
    }

