如何实例化并将（附加）故事板推入我的应用程序？

Question

我的应用主要是在没有故事板的情况下构建的。 但是，我只创建了一个用户注册。

此故事板由包含2个视图控制器的导航控制器组成。 第一个被称为“FirstVC”，一个被称为“SecondVC”（这个不会用于我的问题）。

我正在尝试将其推送到AppDelegate.m文件中（尝试各种方式，见下文）但我的屏幕始终是黑色的。

尝试1

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {


    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];

    UIStoryboard *sb = [UIStoryboard storyboardWithName:@"FirstRegistration" bundle:nil];
    FirstVC *fvc = [sb instantiateViewControllerWithIdentifier:@"FirstVC"];
    UINavigationController *navController =(UINavigationController *)self.window.rootViewController;
    [navController pushViewController:fvc animated:YES];
   return YES;

}

尝试2

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {


    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];

    UIStoryboard *sb = [UIStoryboard storyboardWithName:@"FirstRegistration" bundle:nil];
    FirstVC *fvc = [sb instantiateViewControllerWithIdentifier:@"FirstVC"];
    self.window.rootViewController = fvc;
    return YES;
}

注意：我已将FirstVC场景设置为标识符Custom Class部分中的FirstVC，并将故事板ID设置为FirstVC。但是我没有触及NavigationController场景，我应该将自定义类设置为UINavigationController吗？

Answer 1

你可以尝试添加这一行吗

[self.window makeKeyAndVisible];

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

    UIStoryboard *sb = [UIStoryboard storyboardWithName:@"FirstRegistration" bundle:nil];
    FirstVC *fvc = [sb instantiateViewControllerWithIdentifier:@"FirstVC"];
    self.window.rootViewController = fvc;
    [self.window makeKeyAndVisible]; //**Add this**
    return YES;
}