Question

我有关于自定义UITabBarItem的问题

现在，我在MyAppDelegate定制UITabbarcontroller是：

-(void)configureiPhoneTabBar
{
    tabViewController  = (UITabBarController *)self.window.rootViewController;
    UIViewController *controller1 = [[tabViewController viewControllers] objectAtIndex:0];
    [self configureTabBarItemWithImageName:@"home_ON.png" : @"home.png" andText:@"Home" forViewController:controller1];

    UIViewController *controller2 = [[tabViewController viewControllers] objectAtIndex:1];
    [self configureTabBarItemWithImageName:@"tvChannel_ON.png" : @"tvChannel.png" andText:@"TV" forViewController:controller2];
}

-(void)configureTabBarItemWithImageName:(NSString*)imageName1 : (NSString*)imageName2 andText:(NSString *)itemText forViewController:(UIViewController *)viewController
{
    UIImage* icon1 = [UIImage imageNamed:imageName1];
    UIImage* icon2 = [UIImage imageNamed:imageName2];

    UITabBarItem *item1 = [[UITabBarItem alloc] initWithTitle:itemText image:icon1 tag:0];
    [item1 setTitleTextAttributes:@{ UITextAttributeTextColor : [UIColor whiteColor] }
                         forState:UIControlStateNormal];
    [item1 setFinishedSelectedImage:icon1 withFinishedUnselectedImage:icon2];
    [viewController setTabBarItem:item1];
}

我在UINavigationController中使用UITabbarcontroller，我无法从appdelegate定制uitabaritem，如果你在UITabBarController中运行代码并检查“initial”，界面显示为true，但是当在UINavigationController中检查“initial”时非常困难这样做

Answer 1

如果从登录视图控制器启动应用程序，则可以从该初始viewController配置tabBarController。您可以在prepareForSegue中执行此操作，因为您将在segue.destinationViewController ...中找到指向tabBarController的指针...

- (void) prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
    {
        [self configureiPhoneTabBar:segue.destinationViewController];
    }

将tabBarViewController配置代码移动到此viewController ...

 -(void)configureiPhoneTabBar:(UITabBarController*)tabViewController
 {
        // tabViewController  = (UITabBarController *)self.window.rootViewController;
    UIViewController *controller1 = [[tabViewController viewControllers] objectAtIndex:0];
        //...etc...

或将configureiPhoneTabBar:发送给您的应用代理进行配置（但实际上最好将代码保留在您的应用代理之外）。

更好的是你可以继承UITabBarViewController并将配置代码放在那里，由viewDidLoad触发：

- (void)viewDidLoad
{
    [super viewDidLoad];
    [self configureiPhoneTabBar];
}


-(void)configureiPhoneTabBar
  {
    UIViewController *controller1 = [[self viewControllers] objectAtIndex:0];

        ...etc...

作为另一种选择，您可以在加载到标签栏的相应viewControllers中找到配置代码。

Answer 2

移动代码以将标签栏自定义为LoginViewController（它是一个分隔到标签栏控制器的标签栏）。我将此代码添加到该文件的末尾：

-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
    if ([segue.identifier isEqualToString:@"idenLogin"]) {
        UITabBarController *tabViewController  = segue.destinationViewController;
        UIViewController *controller1 = [[tabViewController viewControllers] objectAtIndex:0];
        [self configureTabBarItemWithImageName:@"home_ON.png" : @"home.png" andText:@"Home" forViewController:controller1];
        UIViewController *controller2 = [[tabViewController viewControllers] objectAtIndex:1];
        [self configureTabBarItemWithImageName:@"tvChannel_ON.png" : @"tvChannel.png" andText:@"TV" forViewController:controller2];
    }
}


-(void)configureTabBarItemWithImageName:(NSString*)imageName1 : (NSString*)imageName2 andText:(NSString *)itemText forViewController:(UIViewController *)viewController {
    UIImage* icon1 = [UIImage imageNamed:imageName1];
    UIImage* icon2 = [UIImage imageNamed:imageName2];

    UITabBarItem *item1 = [[UITabBarItem alloc] initWithTitle:itemText image:icon1 tag:0];
    [item1 setTitleTextAttributes:@{ UITextAttributeTextColor : [UIColor whiteColor] }
                         forState:UIControlStateNormal];
    [item1 setFinishedSelectedImage:icon1 withFinishedUnselectedImage:icon2];
    [viewController setTabBarItem:item1];
}

故事板 - 如何使用UINavigationController内的UITabbarController自定义UITabbarItem

2 个答案: