Question

我正在开发一个应用程序，我正在使用标签栏控制器。当应用程序打开时，它应该只显示一个标签栏项目＆＃34;餐厅＆＃34;当我从任何一家餐馆的菜单中选择一些食品时，应该显示另一个名为项目的标签栏视图控制器。请帮我解决这个问题。

提前致谢。

Answer 1

这是一种方式：

根据需要创建应用程序，并确保在添加TabBarController时，应该只有一个标签项（删除其他项目，默认情况下在添加tabbarcontroller时添加）
< / LI>
创建UITabBarController
从故事板分配所有控制器的类以及分配特定的故事板标识符
声明BOOL类型的全局属性（在用户默认值或您要维护的位置）我已添加到AppDelegate.h
```
@property (assign, nonatomic) BOOL isAddNew;
```

现在，您要在tabor中添加（显示）新标签，添加代码，我的代码为：

- (IBAction)addNewTab:(id)sender
{
    AppDelegate *appDelegate = (AppDelegate *)[[UIApplication sharedApplication] delegate];
    appDelegate.isAddNew = TRUE;
    [self.tabBarController viewDidLoad];
}

然后转到自定义tabbarcontroller（在步骤2中创建 - ＆gt; UITabBarController的子类），我的班级为.h
```
#import <UIKit/UIKit.h>

@interface TabViewController : UITabBarController

@end
```

.m是

#import "TabViewController.h"
#import "AppDelegate.h"
#import "ViewController2.h"
#import "ViewController3.h"

@interface TabViewController ()
{
    AppDelegate *appDelegate;
}
@end

@implementation TabViewController

- (void)viewDidLoad
{
    [super viewDidLoad];

    appDelegate = (AppDelegate *)[[UIApplication sharedApplication] delegate];

    if (appDelegate.isAddNew == TRUE)
    {
        ViewController2 *view2 = [self.storyboard instantiateViewControllerWithIdentifier:@"ViewController2"];
        //ViewController3 *view3 = [self.storyboard instantiateViewControllerWithIdentifier:@"ViewController3"];

        NSMutableArray *tabViewControllers = [self.viewControllers mutableCopy];   //  [[NSMutableArray alloc] init];
        [tabViewControllers addObject:view2];
        //[tabViewControllers addObject:view3];

        [self setViewControllers:tabViewControllers];

        //can't set this until after its added to the tab bar

        // ------ First way ------
        view2.tabBarItem = [[UITabBarItem alloc] initWithTitle:@"Second" image:[UIImage imageNamed:@"selectimg.png"] tag:1];

        // ------ Second way ------
        view2.tabBarItem = [[UITabBarItem alloc] initWithTitle:@"Second" image:[UIImage imageNamed:@"deselectimg"] selectedImage:[UIImage imageNamed:@"selectimg.png"]];

        // ------ Third way ------
        view2.tabBarItem = [[UITabBarItem alloc] init];
        view2.tabBarItem.selectedImage = [[UIImage imageNamed:@"selectimg.png”]imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];
        view2.tabBarItem.image = [[UIImage imageNamed:@"deselectimg.png”]imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal ];
        view2.tabBarItem.title = @"Second";

        //view3.tabBarItem = [[UITabBarItem alloc] initWithTitle:@"Third" image:[UIImage imageNamed:@"third.png"] tag:2];

        [appDelegate.window setRootViewController:self];
    }
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

应用程序栏

1 个答案: