ios5 - 带有容器控制器和 UINavigationController 的 UIViewController 层次结构中出现意外的 UIView 偏移

Question

我有一个带有许多子视图控制器的 UINavigationController，其中一些是容器控制器。最后添加的子 UIViewController（绿色背景）的 UIView 框架布局有它的父背景（黄色），当它不应该时。

如何布局所有内容，以便所有视图都适合导航栏下方的屏幕范围，而不会出现奇怪的偏移？

UIViewController 层次结构，从我的 AppDelegate 开始：

UINavigationController rootViewController:FrontFacadeViewController < UIViewController
    view (0,0) dim:(320x460)

    => StandardCoverViewController < UIViewController
    added as addSubview of FrontFacadeViewController's view]    
    view: (0,0) dim:(320x460)       

        => ConfigurationViewController < UIViewController
        added by pushing onto self.navigationController
        view: (0,20) (320x460)

            => GearViewController < UIViewController
            added as subview of ConfigurationViewController's view 
            view: (0,0) (320x416)

以下是所有视图控制器的创建方式：

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    FrontFacadeViewController *frontController = [[FrontFacadeViewController alloc]
        initWithBundle:[NSBundle mainBundle]];

    _appNavigationController = [[UINavigationController alloc] 
        initWithRootViewController:frontController];        
}

FrontFacadeViewController：

// FrontFacadeViewController determines a particular view controller to present 
// based on some business logic.
// Because of this, it adds child UIViewControllers using container controllers.
//
- (void)viewDidLoad {
    StandardCoverViewController *controller = [StandardCoverViewController alloc] initWithNibName:nil bundle:self.nibBundle];

    [self addChildViewController:controller];
    [controller didMoveToParentViewController:self];    
    [self.view addSubview:controller.view];    
    [controller didMoveToParentViewController:self];    
}

- (IBAction)onButtonPress {
    ConfigurationViewController *controller = [[ConfigurationViewController alloc] initWithNibName:nil bundle:self.nibBundle];
    [self.navigationController pushViewController:controller animated:YES];        
}   

ConfigurationViewController：（黄色背景）

- (void)viewDidLoad {
    [self.view setBackgroundColor:[UIColor yellowColor]];
    GearViewController *controller = [[GearViewController alloc] initWithNibName:nil bundle:self.nibBundle];
    [self addChildViewController:controller];
    [self.view addSubview:controller.view];
    [controller didMoveToParentViewController:self];    
}

GearViewController：（绿色背景）

- (void)viewDidLoad {
    [self.view setBackgroundColor:[UIColor greenColor]];
    // nothing special
}

我做这一切都错了吗？