通过代码添加视图6（2）

下面手添加一个view：

1。创建

2，

//  AppDelegate.m

#import "AppDelegate.h"

#import "MainViewController.h"

@interface AppDelegate ()

@end

@implementation AppDelegate

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

    // Override point for customization after application launch.

    

    //0，创建窗口

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

    self.window.backgroundColor = [UIColor whiteColor];

    

    

    //1，显示窗口方法1 :添加子窗口的方式显示

    MainViewController *addfirstview=[[MainViewController alloc]init];

    [addfirstview.view setBackgroundColor:[UIColor blueColor]];

    //把addfirstview添加到窗口上

    [self.window addSubview:addfirstview.view];

        //显示窗口

    [self.window makeKeyAndVisible];

    return YES;

}