IOS学习 UIViewController 视图控制器的创建

#import "AppDelegate.h"

#import "RootViewController.h"

@interface AppDelegate ()

@end

@implementation AppDelegate

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {

    // Override point for customization after application launch.

    

    //将视图控制器添加到UIWindow上 代码创建

//    UIViewController *mainViewController = [[UIViewController alloc]init];

//    mainViewController.view.backgroundColor = [UIColor redColor];

//    self.window.rootViewController = mainViewController;

//    [mainViewController release];

    /*

    RootViewController *rootViewController = [[RootViewController alloc]init];

    rootViewController.view.backgroundColor = [UIColor redColor];

    self.window.rootViewController = rootViewController;

    [rootViewController release];

    */

     //nib创建1

//    RootViewController *rootViewController = [[RootViewController alloc]initWithNibName:@"View" bundle:nil];

//    self.window.rootViewController = rootViewController;

//    [rootViewController release];

    

    //nib创建2

    RootViewController *rootViewController = [[RootViewControlleralloc]init];

    self.window.rootViewController = rootViewController;

    [rootViewController release];

    

    //旧方法

//    [self.window addSubview:rootViewController.view];

    

    //创建视图控制器时不要在初始化方法中

    

    return YES;

}

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