////  AppDelegate.m//  07-控制器View的创建#import "AppDelegate.h"@interface AppDelegate ()@end@implementation AppDelegate- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {    // Override point for customization after application launch.            self.window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];        UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"Main" bundle:nil];        // 加载箭头指向的控制器    UIViewController *vc = [storyboard instantiateInitialViewController];            self.window.rootViewController = vc;        [self.window makeKeyAndVisible];        return YES;}@end

////  ViewController.m//  07-控制器View的创建#import "ViewController.h"@interface ViewController ()@end@implementation ViewController// loadView作用：自定义控制器的view// loadView什么时候调用：第一次使用控制器的view的时候调用// 注意：在这个方法中如果没有自定义view,就不能获取控制器的view// 一旦重写了这个方法，就不要调用[super loadView]// 如果重写了这个方法，就不会去加载storyboard描述的控制器的View- (void)loadView{  //  self.view.backgroundColor = [UIColor redColor];    //    // 创建控制器view    self.view = [[UIView alloc] initWithFrame:[UIScreen mainScreen].bounds];//        self.view.backgroundColor = [UIColor purpleColor];}//- (UIView *)view//{//    if (_view == nil) {//        [self loadView];//        //        [self viewDidLoad];//    }//    return _view;//}#pragma mark - 直接不实现就是系统默认的做法//- (void)loadView//{//    // super ->  UIViewController//    // 系统默认的做法,一定不要这样写//    [super loadView];//    //}- (void)viewDidLoad {    [super viewDidLoad];    // Do any additional setup after loading the view, typically from a nib.}- (void)didReceiveMemoryWarning {    [super didReceiveMemoryWarning];    // Dispose of any resources that can be recreated.}@end