用Objective-c语言纯代码写一个签到的日期界面

好的，以下是用Objective-C纯代码实现的签到日期界面。实现的界面包括一个导航栏、一个显示当前日期的标签和一个签到按钮。

ViewController.h文件：

#import <UIKit/UIKit.h>

@interface ViewController : UIViewController

@end

ViewController.m文件：

#import "ViewController.h"

@interface ViewController ()

@property (nonatomic, strong) UILabel *dateLabel;

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    
    // 设置导航栏标题
    self.navigationItem.title = @"签到";
    
    // 设置背景颜色
    self.view.backgroundColor = [UIColor whiteColor];
    
    // 创建并添加日期标签
    self.dateLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 200, 50)];
    self.dateLabel.center = CGPointMake(self.view.frame.size.width/2, self.view.frame.size.height/2 - 50);
    self.dateLabel.textAlignment = NSTextAlignmentCenter;
    self.dateLabel.textColor = [UIColor blackColor];
    [self.view addSubview:self.dateLabel];
    
    // 更新日期标签的文本
    [self updateDateLabel];
    
    // 创建并添加签到按钮
    UIButton *checkInButton = [UIButton buttonWithType:UIButtonTypeSystem];
    checkInButton.frame = CGRectMake(0, 0, 200, 50);
    checkInButton.center = CGPointMake(self.view.frame.size.width/2, self.view.frame.size.height/2 + 50);
    [checkInButton setTitle:@"签到" forState:UIControlStateNormal];
    [checkInButton addTarget:self action:@selector(checkInButtonClicked:) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:checkInButton];
}

// 更新日期标签的文本
- (void)updateDateLabel {
    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
    formatter.dateFormat = @"yyyy年MM月dd日";
    self.dateLabel.text = [formatter stringFromDate:[NSDate date]];
}

// 签到按钮点击事件
- (void)checkInButtonClicked:(UIButton *)sender {
    // TODO: 处理签到逻辑
    
    // 更新日期标签的文本
    [self updateDateLabel];
}

@end

在AppDelegate.m文件中，将ViewController设置为根视图控制器：

#import "AppDelegate.h"
#import "ViewController.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];
    
    ViewController *viewController = [[ViewController alloc] init];
    UINavigationController *navigationController = [[UINavigationController alloc] initWithRootViewController:viewController];
    self.window.rootViewController = navigationController;
    
    [self.window makeKeyAndVisible];
    
    return YES;
}

这样就完成了一个简单的签到日期界面的实现。运行程序后，可以看到一个带有日期标签和签到按钮的界面。点击签到按钮后，日期标签上的日期会更新为当前日期。