iphone - 是否可以将当前的 Modal ViewController 设为 UINavigationController？

Question

我正在尝试在应用程序启动时创建一个 presentModalViewController。我可以让 presentModalViewController 正常运行，但是当我尝试将其设置为 UINavigation Controller 时，我看到的只是一个空白的 UINavigationController。

我的类(class)概述定义如下:

#import <UIKit/UIKit.h>
@class Login;

@interface Overview : UINavigationController {

}

-(IBAction) btnRegistrationPressed;
-(IBAction) btnLoginPressed;


@end

然后在委托(delegate)中我这样做:

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

    // Override point for customization after application launch.

    // Add the tab bar controller's view to the window and display.
    [self.window addSubview:tabBarController.view];

    Overview *overviewViewController = [[Overview alloc] initWithNibName:@"Overview" bundle:nil];

    [self.tabBarController presentModalViewController:overviewViewController animated:YES];
    [overviewViewController release];
    [self.window makeKeyAndVisible];

    return YES;
}

我还有一个 Overview.xib，我在其中从库中拖入了一个 UiNavigation Controller 。下面的 View Controller 被设置为一个名为 test 的类，它将在屏幕上显示一条消息。

当我启动时，我看到的只是一个空白的 UINavigationController。

有任何想法吗？

Answer 1

你试过像下面这样

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

// Override point for customization after application launch.

// Add the tab bar controller's view to the window and display.
[self.window addSubview:tabBarController.view];


Overview *overviewViewController = [[Overview alloc] initWithNibName:@"Overview" bundle:nil];

 UINavigationController *nav_obj = [[UINavigationController alloc] initWithRootViewController:overviewViewController ];

[self.tabBarController presentModalViewController:nav_obj  animated:YES];
[overviewViewController release];
[self.window makeKeyAndVisible];

return YES;

}