底部导航控制器

Xiaoxi *xi=[[Xiaoxi alloc]init];

//设置导航

UINavigationController *nav=[[UINavigationController alloc]initWithRootViewController:xi];

Pengyou *p=[[Pengyou alloc]init];

//设置导航

UINavigationController *nav1=[[UINavigationController alloc]initWithRootViewController:p];

Geren *g=[[Geren alloc]init];

//设置导航

UINavigationController *nav2=[[UINavigationController alloc]initWithRootViewController:g];

UITabBarItem *ba=[[UITabBarItem alloc]initWithTitle:@"新闻" image:[UIImage imageNamed:@"u34.png"] selectedImage:[UIImage imageNamed:@"u34.png"]];

nav.tabBarItem=ba;

UITabBarItem *ba2=[[UITabBarItem alloc]initWithTitle:@"推荐" image:[UIImage imageNamed:@"111"] selectedImage:[UIImage imageNamed:@"111"]];

nav1.tabBarItem=ba2;

UITabBarItem *ba3=[[UITabBarItem alloc]initWithTitle:@"直播" image:[UIImage imageNamed:@""] selectedImage:[UIImage imageNamed:@""]];

nav2.tabBarItem=ba3;

   UITabBarController *tab = [[UITabBarController alloc]init];

tab.viewControllers = @[nav,nav1,nav2];