未显示iPhone navigationController

我的导航视图有一个非常奇怪的行为。我想要的是,在我的主视图中,用户可以点击一个按钮,这将引导他进入带有应用程序设置的视图。

下面是负责导航的代码:

    @interface AppDelegate : NSObject  {
    UIWindow *window;
    ViewController *viewController; // My Main View Controller
    UINavigationController *navigationController; } 

    @property (nonatomic, retain) IBOutlet UIWindow *window;
    @property (nonatomic, retain) IBOutlet ViewController *viewController;
    @property (nonatomic, retain) IBOutlet UINavigationController *navigationController;

AppDelegate.m公司

@synthesize viewController;
@synthesize window;
@synthesize navigationController;

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {    

    [window addSubview:viewController.view];
    [window addSubview:navigationController.view];
    [window makeKeyAndVisible];
    return YES;
}

视图控制器.h

#import 
#import "optionsViewController.h" // the 'settings' view controller

@class AppDelegate;

@interface ViewController : UIViewController {
    AppDelegate *appDelegate;

- (IBAction)showOptionsViewController:(UIBarButtonItem *)sender {
//  optionsController.theSubjectID = self.theSubjectID;
//  [self presentModalViewController:self.optionsController animated:YES];


    optionsViewController *optionsController= [[optionsViewController alloc] initWithNibName:@"optionsViewController" bundle:nil];
    optionsController.theSubjectID = self.theSubjectID;
    [self.navigationController pushViewController:optionsController animated:YES];
    [optionsController release];

}

我的optionsController是“普通”UIViewController。如您所见,我将选项控制器的负载从模式更改为导航。是不是我错过了什么?

干杯,任