UISplitViewController in a TabBar ( UITabBarController )?

Using the interface builder, create a split view controller and a tab bar controller and link them to your outlets:

@property (nonatomic, retain) IBOutlet UITabBarController *tabBarController;
@property (nonatomic, retain) IBOutlet UISplitViewController *splitViewController;

In your app delegate didFinishLaunchingWithOption, assign your split view controller to the tab bar controller:

splitViewController.tabBarItem = [[[UITabBarItem alloc] initWithTitle:@"Title" image:nil tag:0] autorelease];
NSArray *controllers = [NSArray arrayWithObjects:splitViewController,  /* other controllers go here */ nil];
tabBarController.viewControllers = controllers;
[window addSubview:tabBarController.view];
[window makeKeyAndVisible];

This will create a tab bar controller (with only 1 tab in this case), which is displayed correctly in all orientations.

I've written up a subclass for the UISplitViewController that will listen for changes to device orientation and orient itself accordingly. With this class, I can now place split views within a UITabBarController and each split view will behave correctly upon rotation, even if it's not the frontmost tab. I've successfully deployed this in TexLege and it was approved for use in the App Store, but your mileage may vary. Please see the repository at Github.

Feel free to fork and modify it, and I'm always interested in hearing comments (or complaints) about it. https://github.com/grgcombs/IntelligentSplitViewController

I made a sample application. and found we can do it programmatically like:

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

        NSMutableArray *array = [NSMutableArray array];

        NSMutableArray *tabArray = [NSMutableArray array]; 

        UISplitViewController *splitViewConntroller = [[UISplitViewController alloc] init];

        MainViewController *viewCont = [[MainViewController alloc] initWithNibName:@"MainViewController" bundle:nil];
        [array addObject:viewCont];
        [viewCont release];

        viewCont = [[DetailViewController alloc] initWithNibName:@"DetailViewController" bundle:nil];
        [array addObject:viewCont];
        [viewCont release];




        [splitViewConntroller setViewControllers:array];

        [tabArray addObject:splitViewConntroller];

        [splitViewConntroller release];

        array = [NSMutableArray array];

        splitViewConntroller = [[UISplitViewController alloc] init];

        viewCont = [[MainViewController alloc] initWithNibName:@"MainViewController" bundle:nil];
        [array addObject:viewCont];
        [viewCont release];

        viewCont = [[DetailViewController alloc] initWithNibName:@"DetailViewController" bundle:nil];
        [array addObject:viewCont];
        [viewCont release];

        [splitViewConntroller setViewControllers:array];

        [tabArray addObject:splitViewConntroller];

        [splitViewConntroller release];

        // Add the tab bar controller's current view as a subview of the window
        [tabBarController setViewControllers:tabArray];

        [window addSubview:tabBarController.view];
        [window makeKeyAndVisible];

        return YES;
    }

Hope this helps.