It's generally used to switch between various subtasks, views or models within the same view.
Example for tab bar is shown below.
Step 1 − Create a new project and select Tabbed Application instead of the View Based application and click next, Give the project name and select create.
Step 2 − Here two view controllers are created by default and a tab bar is added to our application.
Step 3 − The AppDelegate.m didFinishLaunchingWithOptions method is as follows −
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions { self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]]; // Override point for customization after application launch. UIViewController *viewController1 = [[FirstViewController alloc] initWithNibName:@"FirstViewController" bundle:nil]; UIViewController *viewController2 = [[SecondViewController alloc] initWithNibName:@"SecondViewController" bundle:nil]; self.tabBarController = [[UITabBarController alloc] init]; self.tabBarController.viewControllers = @[viewController1, viewController2]; self.window.rootViewController = self.tabBarController; [self.window makeKeyAndVisible]; return YES; }
Step 4 − Here, two view controllers are allocated and made as view controllers of our tab bar controller.
Step 5 − When we run the application, we'll get the following output −