1. 创建一个空iOS应用程序(Empty Application).
2. 添加加控制器类. 修改控制器类的viewDidLoad
1 - (void)viewDidLoad
2 {
3 [super viewDidLoad];
4 //创建标题
5 UILabel *header = [[UILabel alloc] init];
6 header.text = @"欢迎来到我的世界!";
7 header.textAlignment = NSTextAlignmentCenter;
8 [self.view addSubview: header];
9
10 self.statusLabel = [[UILabel alloc] init];
11 self.statusLabel.text = @"准备就绪!";
12 [self.view addSubview: self.statusLabel];
13
14
15 //添加自动布局约束
16 UILabel *statusLabel = self.statusLabel;
17 [header setTranslatesAutoresizingMaskIntoConstraints: NO];
18 [statusLabel setTranslatesAutoresizingMaskIntoConstraints: NO];
19
20 NSMutableArray *contraits = [NSMutableArray array];
21 NSMutableDictionary *metrics = [[NSMutableDictionary alloc] initWithObjectsAndKeys:@5, @"HPadding", @5, @"VPadding", @20, @"TopMargin", nil];
22 NSDictionary *views = NSDictionaryOfVariableBindings(header, statusLabel);
23 [contraits addObjectsFromArray:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|-HPadding-[header]-HPadding-|" options:0 metrics:metrics views:views]];
24 [contraits addObjectsFromArray:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|-HPadding-[statusLabel]-HPadding-|" options:0 metrics:metrics views:views]];
25 [contraits arrayByAddingObjectsFromArray:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|-HPadding-[statusLabel]-HPadding-|" options:0 metrics:metrics views:views]];
26 [contraits addObjectsFromArray:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-TopMargin-[header]-(>=0)-[statusLabel]-VPadding-|" options:0 metrics:metrics views:views]];
27
28 [self.view addConstraints: contraits];
29
30 }
3. 修改AppDelegate.m文件
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
// Override point for customization after application launch.
self.window.backgroundColor = [UIColor whiteColor];//加入控制器
self.window.rootViewController = [[DemoViewController alloc] initWithNibName:nil bundle:nil];[self.window makeKeyAndVisible];
return YES;
}
4. 运行程序, 得到如下效果
iOS: 学习笔记, 添加一个带界面约束的控制器,布布扣,bubuko.com
时间: 2024-08-29 18:30:41