UI程式啟動之application

1 建立UIWindow  //一個應用程式隻有一個UIWindow

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

 讓UIWindow顯示出來(讓視窗成為主視窗 并且顯示出來)

[self.window makeKeyAndVisible];

2 建立控制器

 JMViewController *vc = [[JMViewController alloc] init];

2.1第一種建立方式

    NJViewController *vc = [[NJViewController alloc] init];

    vc.view.backgroundColor = [UIColor redColor];

2.2第二種建立方式

 NJViewController *vc = [[NJViewController alloc] init];

 // 加載UIStoryboard(注意:僅僅是加載名稱叫做Test的storyboard, 并不會建立storyboard重的控制器以及控件)

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

// 建立storyboard中箭頭指向的控制器

  NJViewController *vc = [storyboard instantiateInitialViewController];

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

2.3第三種建立方式

   NJViewController *vc = [[NJViewController alloc] initWithNibName:@"One" bundle:nil];

   self.window.rootViewController = vc;

3.讓UIWindow顯示出來

    [self.window makeKeyAndVisible];

    return YES;