iphone - 如何启动有关设备类型的特定 View

Question

我正在尝试在启动时启动 3 个 View 中的 1 个。我要启动的 View 取决于设备类型。这是我目前在 AppDelegate.m

中的内容

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
    // Override point for customization after application launch.
    if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone && [UIScreen mainScreen].bounds.size.height == 568.0) {
        self.viewController = [[ViewController alloc] initWithNibName:@"ViewController_Portrait5" bundle:nil];
    }

    else if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone && [UIScreen mainScreen].bounds.size.height == 480.0) {
        self.viewController = [[ViewController alloc] initWithNibName:@"ViewController_Portrait4" bundle:nil];
    }

    else {
        self.viewController = [[ViewController alloc] initWithNibName:@"ViewController_PortraitPad" bundle:nil];
    }
}

问题是，当我启动应用程序时，出现黑屏。

Answer 1

您没有在窗口上设置 Controller ，在该方法的末尾添加:

self.window.rootViewController = self.viewController;
[self.window makeKeyAndVisible];