Question

My app requires one set of tabs on the initial view, the last tab item is reserved for an in-app purchase once the user selects. However, once the user makes the in-app purchase I would like a new set of tabs to appear. I would like for the user to be able to switch back and forward between the free part of the app and the in-app purchase part of the app with different tab bars. For example:

“TabBar1” to have “TabItem 1”, “TabItem 2”, “TabItem 3”, and “TabItem 4” for my Free App, when user selects “TabItem 4” …a welcome or in-app purchase screen will appear. If user makes the in-app purchase, “TabBar2” appears with “TabItem 1”, “TabItem 5”, “TabItem 6”, and “TabItem4”. “TabItem1” will bring you back to Free part of app and “TabBar1” when selected again. Hope I didnt confuse…How do you accomplish this? Thanks for the help.

I forgot to add that this Tabbar is to be combined with a Navigation controller as well.

Answer 1

you can change the views of root tabbarcontroller anytime you want, also you can change tabbaritems title & icons. Here’s an example:

MyAppDelegate *appController = (MyAppDelegate *)[[UIApplication sharedApplication] delegate];
    // Setting 1st tab + view + icon
    ViewController1 *viewController1 = [[ViewController1 alloc] initWithNibName:@"ViewController1" bundle:nil];
favoritesController.title = @"Tab1 Title";
UINavigationController *navigationTab1Controller = [[[UINavigationController alloc] initWithRootViewController: viewController1] autorelease];
UITabBarItem    *anItem = [[[UITabBarItem alloc] initWithTabBarSystemItem:UITabBarSystemItemFavorites tag:0] autorelease];
navigationTab1Controller.tabBarItem = anItem;

    // Setting 2st tab + view + icon
ViewController2 *viewController2 = [[ViewController2 alloc] initWithNibName:@"ViewController2" bundle:nil];
searchController.title = @"Tab2 Title";
UINavigationController *navigationTab2Controller = [[[UINavigationController alloc] initWithRootViewController:searchController] autorelease];
UITabBarItem    *anItem1 = [[[UITabBarItem alloc] initWithTabBarSystemItem:UITabBarSystemItemSearch tag:1] autorelease];
navigationTab2Controller.tabBarItem = anItem1;

    // Now setting the array of tab views, each one attached to its navigation controller
NSArray *array = [[NSArray alloc] initWithObjects:self.navigationController, navigationTab1Controller, navigationTab2Controller, nil];
[appController.tabBarController setViewControllers:array animated:NO];
appController.tabBarController.selectedViewController = self.navigationController;
UITabBarItem    *anItem2 = [[[UITabBarItem alloc] initWithTitle:@"Tab3 Title" image:[appController  thumbnailImage:@"image"] tag:2] autorelease];
self.navigationController.tabBarItem = anItem2;

I’m changing the set of views and tabs, depending of the state of my application. Hopefully it helps

EDIT: function thumbnailImage is a function I wrote for caching images and avoid memory leaks, you can use imageNamed instead or other technique that retrieves an image from a bundle.