通过storyboard创建控制器

一、通过storyboard创建

UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"Main" bundle:nil];

UIViewController *vc = [storyboard instantiateInitialViewController];

UIViewController *vc = [storyboard instantiateViewControllerWithIdentifier:@"red"];

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
// Override point for customization after application launch.

// 创建窗口
self.window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];

// 创建窗口的跟控制器
// 加载storyboard
// storyboard文件名，不需要带后缀
// nil:  [NSBundle mainBundle]
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"Main" bundle:nil];
// 通过storyboard创建控制器
// instantiateInitialViewController：加载箭头指向的控制器
//    UIViewController *vc = [storyboard instantiateInitialViewController];

UIViewController *vc = [storyboard instantiateViewControllerWithIdentifier:@"green"];

NSLog(@"%@",[vc class]);
self.window.rootViewController = vc;

// 显示窗口
[self.window makeKeyAndVisible];
return YES;
}