ios Hello World Xocde 12

选择App会为我们创建一个单页应用

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代码模式实现

如果不想使用storyboard实现 我们可以用纯代码方式实现
同样重新创建APP 这次我们用OC语言

创建好后删除storyboard文件
Main interface 中 Main清空

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选择info.plist 删除storyboard Name

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由于SceneDelegate负责UI 所以我们在 SceneDelegate.m新增

#import "ViewController.h"

- (void)scene:(UIScene *)scene willConnectToSession:(UISceneSession *)session options:(UISceneConnectionOptions *)connectionOptions {
        UIWindowScene *windowScene = (UIWindowScene *)scene;
        self.window = [[UIWindow alloc] initWithWindowScene:windowScene];
        self.window.frame = windowScene.coordinateSpace.bounds;
        self.window.backgroundColor = [UIColor whiteColor];
        self.window.rootViewController = [ViewController new];
        [self.window makeKeyAndVisible];
}

在ViewController.m中新增一个label 添加进去

- (void)viewDidLoad {
    [super viewDidLoad];
    CGRect screen = [[UIScreen mainScreen] bounds];
    CGFloat labelWidth = 90;
    CGFloat labelHeight = 20;
    CGFloat labelTopView = 150;
    CGRect frame = CGRectMake((screen.size.width - labelWidth)/2, labelTopView, labelWidth, labelHeight);
    UILabel* label = [[UILabel alloc] initWithFrame: frame];
    
    label.text = @"Hi DDW";
    label.textAlignment = NSTextAlignmentCenter;
    [self.view addSubview:label];
    // Do any additional setup after loading the view.
}

Done

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