模拟ios应用加载页面

1:设置应用程序系统主界面加载接口为空：Main interface=null;

2: 在AppDelegate实现didFinishLaunchingWithOptions方法

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    // Override point for customization after application launch.
    //    初始化窗口
    self.window=[[UIWindow alloc]initWithFrame:[UIScreen mainScreen].bounds];
    //    设置窗口颜色
    self.window.backgroundColor=[UIColor redColor];
    //    自定义viewcontroller
    //    UIViewController *root=[[UIViewController alloc]init];
    //    root.view.backgroundColor=[UIColor blueColor];
    //    创建UIStoryboard对象
    UIStoryboard *storybord= [UIStoryboard storyboardWithName:@"Main" bundle:nil];
    //    1:创建指定storybordId的viewcontroller
    UIViewController *root=[storybord instantiateViewControllerWithIdentifier:@"green"];
    //     2:创建指定默认的viewcontroller
    //    UIViewController *root2=[storybord instantiateInitialViewController];
    //    设置rootViewController
    self.window.rootViewController=root;
    //显示窗口
    [self.window makeKeyAndVisible];
    return YES;
}