How to change default ViewController of UITabBarController

问题

I create basic TabBarController with 2 ViewControllers. It worked but it have bug and i want something about it.

Problem1.

When I run (default ViewController is FirstViewController) name of SecondViewController in TabBar is not appear.

I want following this picture.

Problem2. In my code default view is FirstViewController. If I want to set default view is SecondViewController by Same Tab Bar(FirstView Tab : Left ,and SecondView Tab : Right) following this picture. How to resolve it.

This is my example code

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];

    FirstViewController *firstVC = [[FirstViewController alloc] init];
    UINavigationController *firstNVC = [[UINavigationController alloc] initWithRootViewController:firstVC];
    firstNVC.navigationBar.barStyle = UIBarStyleBlack;

    SecondViewController *secondVC = [[SecondViewController alloc] init];
    UINavigationController *secondNVC = [[UINavigationController alloc] initWithRootViewController:secondVC];
    secondNVC.navigationBar.barStyle = UIBarStyleBlack;

    UITabBarController *tabController = [[UITabBarController alloc]init];
    tabController.navigationItem.hidesBackButton = NO;
    tabController.viewControllers = [NSArray arrayWithObjects:firstNVC, secondNVC, nil];
    tabController.navigationController.navigationBarHidden = NO;

    self.window.rootViewController = tabController;
    self.window.backgroundColor = [UIColor whiteColor];
    [self.window makeKeyAndVisible];
    return YES;
}

Thank You. ^^

回答1:

UIViewController *viewController1 = [[[viewController1 alloc] initWithNibName:@"viewController1" bundle:nil] autorelease];
    UIViewController *viewController2 = [[[viewController2 alloc] initWithNibName:@"viewController2" bundle:nil] autorelease];
    UIViewController *viewController3 = [[[viewController3 alloc] initWithNibName:@"viewController3" bundle:nil] autorelease];


    navControl1=[[UINavigationController alloc]initWithRootViewController:viewController1];
    navControl2=[[UINavigationController alloc]initWithRootViewController:viewController2];
    navControl3=[[UINavigationController alloc]initWithRootViewController:viewController3];

    navControl1.navigationBar.tintColor=[UIColor colorWithRed:0.0 green:0.0 blue:0.0 alpha:0.8];
    navControl2.navigationBar.tintColor=[UIColor blackColor];
    navControl3.navigationBar.tintColor=[UIColor blackColor];

    self.tabBarController = [[[UITabBarController alloc] init] autorelease];
    self.tabBarController.delegate=self;
    self.tabBarController.viewControllers = [NSArray arrayWithObjects:navControl2,navControl1,navControl3, nil ];

    [[[[self.tabBarController tabBar] items] objectAtIndex:2] setFinishedSelectedImage:[UIImage imageNamed:@""] withFinishedUnselectedImage:[UIImage imageNamed:@""]];
    [[[[self.tabBarController tabBar] items] objectAtIndex:0] setTitle:@"1"];
    [[[[self.tabBarController tabBar] items] objectAtIndex:0] setImage:[UIImage imageNamed:@"tab2.png"]];
    [[[[self.tabBarController tabBar] items] objectAtIndex:1] setTitle:@"2"];
    [[[[self.tabBarController tabBar] items] objectAtIndex:1] setImage:[UIImage imageNamed:@"tab11.png"]];
    [[[[self.tabBarController tabBar] items] objectAtIndex:2] setTitle:@"3"];
    [[[[self.tabBarController tabBar] items] objectAtIndex:2] setImage:[UIImage imageNamed:@"tab5.png"]];

    [self.tabBarController.tabBar setSelectionIndicatorImage:[UIImage imageNamed:@"trans.png"]];

    UIImage* tabBarBackground = [UIImage imageNamed:@""];
    [[UITabBar appearance] setBackgroundImage:tabBarBackground];
    [[UITabBar appearance] setSelectionIndicatorImage:[UIImage imageNamed:@"trans.png"]];

回答2:

Problem2. If I want to set default view is SecondViewController by Same Tab Bar(FirstView Tab : Left ,and SecondView Tab : Right). How to resolve it.

Solution:

[self.tabBarController setSelectedIndex:1];

回答3:

Problem 1:

try to set a title for the view controllers.

Problem 2:

You just set selected index of the tabBarController to 1, that should do it.

回答4:

Problem1

You haven't set tabbarItem for each navigation controller, I think you should set up a UITabBarItem with title first, then assign it to tabbarItem property to navigation controller.

Problem2

Just as @Kumar says.

来源：https://stackoverflow.com/questions/20966536/how-to-change-default-viewcontroller-of-uitabbarcontroller

标签

ios

objective-c

uitabbarcontroller