tabbarcontroller以编程方式添加了ios但未打开选项卡

Question

我想使用没有导航控制器的标签栏控制器，我希望它以编程方式发生。

我的MainViewController是TabBarController的子类，这里的代码是：

 (void)viewDidLoad
{
    [super viewDidLoad];

    self.viewControllers = [NSArray arrayWithObjects:
                            [self myLikesViewControllerWithTabTitle:@"My Likes" image:[UIImage imageNamed:@"tab_feed.png"]],
                            [self mainStreamViewControllerWithTabTitle:@"Stream" image:nil],
                            [self viewControllerWithTabTitle:@"Messages" image:[UIImage imageNamed:@"tab_messages.png"]], nil];



    self.tabBarController.selectedIndex = 2;

}

其中：

// Create a view controller and setup it's tab bar item with a title and image
-(UIViewController*) viewControllerWithTabTitle:(NSString*) title image:(UIImage*)image
{
    UIViewController* viewController = [[UIViewController alloc] init];
    viewController.tabBarItem = [[UITabBarItem alloc] initWithTitle:title image:image tag:0];
    return viewController;
}

// Create a view controller and setup it's tab bar item with a title and image
-(UIViewController*) myLikesViewControllerWithTabTitle:(NSString*) title image:(UIImage*)image
{
    UIViewController* viewController = [[UIViewController alloc] initWithNibName:@"MyLikesViewController" bundle:nil];
    viewController.tabBarItem = [[UITabBarItem alloc] initWithTitle:title image:image tag:0];
    return viewController;
}

// Create a view controller and setup it's tab bar item with a title and image
-(UIViewController*) mainStreamViewControllerWithTabTitle:(NSString*) title image:(UIImage*)image
{
    UIViewController* viewController = [[UIViewController alloc] initWithNibName:@"StreamViewController" bundle:nil];
    viewController.tabBarItem = [[UITabBarItem alloc] initWithTitle:title image:image tag:0];
    return viewController;
}

我可以看到正在创建的标签，但无论我点击什么，我都看不到我创建的XIB要打开。

我错过了什么吗？

由于