以编程方式在委托中调用故事板

Question

我正在尝试以编程方式调用我的故事板。 我的故事板包含以下内容: [导航控制器] -> [主菜单视图] -> [详细信息视图] "MainMenu"标识符放置在[MainMenuView]中。 我遇到的问题是屏幕显示空白。我需要做什么？ 谢谢。

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{       
    UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil];

    MainMenuView *rootViewController = [storyboard instantiateViewControllerWithIdentifier:@"MainMenu"];

    return YES
}

- RockBaby

Answer 1

您需要先手动创建窗口，然后将rootViewController添加到其中（上一个答案几乎正确）：

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil];

    UIViewController *mainViewController = [storyboard instantiateInitialViewController];

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

    return YES;
}

- sarfata

---

这对于iOS 9来说不再是真的了。 - William Entriken

Answer 2

您需要设置应用程序窗口的rootViewController属性：

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{       
    UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil];
    MainMenuView *rootViewController = [storyboard instantiateViewControllerWithIdentifier:@"MainMenu"];

    self.window.rootViewController = rootViewController;

    return YES;
}

- jonkroll

---

我已经设置了它，但它仍然是空白的。 - RockBaby

@RockBaby：AppDelegate的window属性还没有设置好，你正在给nil发送消息。首先在didFinish...中执行以下操作：self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]]; - Josh