Objective-C：UITabBarController黑屏

Question

在下面，我有一些代码放置在app delegate.m ，并用于在两个ViewController之间创建交流。 选项卡栏的创建工作正常，但是当我选择设置选项卡时，没有视图，只是黑色。

这是代码：

import "ViewController.h"
#import "Settings.h"

@implementation AppDelegate

    - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
    {
        self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
        // Override point for customization after application launch.
        self.viewController = [[ViewController alloc] initWithNibName:@"ViewController" bundle:nil];
        self.window.rootViewController = self.viewController;
        [self.window makeKeyAndVisible];

        UITabBarController *tbc = [[UITabBarController alloc]init];

        ViewController *vc1 = [[ViewController alloc]initWithNibName:@"ViewController" bundle:nil];
        Settings *vc2 = [[Settings alloc]init];

        [vc1.tabBarItem setTitle:@"Browse"];
        [vc2.tabBarItem setTitle:@"Settings"];

        [tbc setViewControllers:[NSArray arrayWithObjects:vc1, vc2, nil]];
        [self.window setRootViewController:tbc];

        return YES;
    }

Answer 1

您这样编写用于设置屏幕的代码

设置* vc2 = [[Settings alloc] init];

用于设置屏幕的笔尖文件在哪里，

一旦尝试这样

UITabBarController * tbc = [[UITabBarController alloc] init];

ViewController *vc1 = [[ViewController alloc]initWithNibName:@"ViewController" bundle:nil];
Settings *vc2 = [[Settings alloc]initWithNibName:@"Settings" bundle:nil];

[vc1.tabBarItem setTitle:@"Browse"];
[vc2.tabBarItem setTitle:@"Settings"];

[tbc setViewControllers:[NSArray arrayWithObjects:vc1, vc2, nil]];
[self.window setRootViewController:tbc];
[self.window makeKeyAndVisible];

Answer 2

尝试：

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

    UITabBarController *tbc = [[UITabBarController alloc]init];

    ViewController *vc1 = [[ViewController alloc]initWithNibName:@"ViewController" bundle:nil];
    Settings *vc2 = [[Settings alloc]init];

    [vc1.tabBarItem setTitle:@"Browse"];
    [vc2.tabBarItem setTitle:@"Settings"];

    [tbc setViewControllers:[NSArray arrayWithObjects:vc1, vc2, nil]];
    [self.window setRootViewController:tbc];
    [self.window makeKeyAndVisible];

    return YES;
}