UITabBar Functionality - ios

Question

TabBar should not be enable any of tabs untill user clicked on any one of tab,
Below is the code I write to display tab bar, But the problem by defaultly it is showing the first tab.
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
// Override point for customization after application launch.
self.window.backgroundColor = [UIColor whiteColor];
[self.window makeKeyAndVisible];
PeopleViewController *peopleViewController = [[PeopleViewController alloc] init];
UINavigationController *nav1 = [[UINavigationController alloc] initWithRootViewController:peopleViewController];
[peopleViewController setTitle:#"People"];
EventsViewController *eventsViewController = [[EventsViewController alloc] init];
UINavigationController *nav2 = [[UINavigationController alloc]initWithRootViewController:eventsViewController];
[eventsViewController setTitle:#"Events"];
ActiveViewController *activeViewController = [[ActiveViewController alloc] init];
UINavigationController *nav3 = [[UINavigationController alloc]initWithRootViewController:activeViewController];
[activeViewController setTitle:#"Active"];
MoreViewController *moreViewController = [[MoreViewController alloc] init];
UINavigationController *nav4 = [[UINavigationController alloc] initWithRootViewController:moreViewController];
[moreViewController setTitle:#"More"];
NSArray *arrViewControllers = [[NSArray alloc] initWithObjects:nav1,nav2,nav3,nav4, nil];
[tabBarController setViewControllers:arrViewControllers];
[self.window addSubview:tabBarController.view];
return YES;
}

Answer 1

Create an IBOutlet for the tab bar (e.g. theTabBar) and use following code:
[theTabBar setSelectedItem:nil];

Answer 2

This is default behavior of UITabBarController, by default first tab is selected.
You have the option to make some other tab to be selected at first instance, but cannot change the default selected to null.
[tabBarController setSelectedIndex:0];
By default selected index is 0, this is first tab, you can change it as per your requirement to 1,2,3.