Question

Hihi all,

I am pretty new in iPhone dev. I have follow some tutorial and created a tabbar application. Below is the code in the appdelegate implementation:

self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
UIViewController *viewController1 = [[ViewController1 alloc] initWithNibName:@"ViewController1" bundle:nil];
UIViewController *viewController2 = [[ViewController2 alloc] initWithNibName:@"ViewController2" bundle:nil];

self.tabBarController = [[UITabBarController alloc] init];
self.tabBarController.viewControllers = [NSArray arrayWithObjects:viewController1, viewController2, nil];

self.window.rootViewController = self.tabBarController;
[self.window makeKeyAndVisible];

Then set the title and the image for the tab in each of the controller implementation.

My problem is that, example, in my viewController1, I need to navigate to viewController3, when I use presentModalViewController method to push the viewController3 in, the tabbar at the bottom will be disappeared.

While I tried to use the app delegate to refer to my tabBarController, and use tabBarController.navigationController pushViewController method, my viewController3 is not being pushed, and seems nothing happens.

I have tried to follow a few tutorial, but it’s all required to drag in the navigationcontroller into the MainWindow.xib, which, in the xcode 4, MainWindow.xib doesn’t exist anymore. How can i create the navigationcontroller from code so that the app can navigate between different view without hiding the tabbar?

Any comment is very much appreciated! Thanks in advance!

🙂

Answer 1

If you want to use a navigation controller, you need to create a navigation controller. Since you’re not using a XIB, you’ll have to create it manually.

Since you want the tab bar to remain visible when you present viewController3, you need to make the navigation controller a child of the tab bar controller.

UIViewController *viewController1 = [[ViewController1 alloc] initWithNibName:@"ViewController1" bundle:nil];
UINavigationController *navController1 = [[UINavigationController alloc] initWithRootViewController:viewController1];
UIViewController *viewController2 = [[ViewController2 alloc] initWithNibName:@"ViewController2" bundle:nil];

self.tabBarController = [[UITabBarController alloc] init];
self.tabBarController.viewControllers = [NSArray arrayWithObjects:
    navController1,
    viewController2,
    nil];

Then when you want to present viewController3, do this:

// in some method of viewController1
[self.navigationController pushViewController:viewController3 animated:YES];