Objective-c纯代码实现签到界面

以下是Objective-C纯代码实现签到界面的示例代码：

#import "CheckInViewController.h"

@interface CheckInViewController ()

@property (nonatomic, strong) UILabel *titleLabel;
@property (nonatomic, strong) UIButton *checkInButton;

@end

@implementation CheckInViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    // 设置背景颜色
    self.view.backgroundColor = [UIColor whiteColor];
    
    // 添加标题
    self.titleLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, 100, self.view.frame.size.width, 30)];
    self.titleLabel.text = @"今日签到";
    self.titleLabel.textAlignment = NSTextAlignmentCenter;
    [self.view addSubview:self.titleLabel];
    
    // 添加签到按钮
    self.checkInButton = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, 150, 50)];
    self.checkInButton.center = self.view.center;
    [self.checkInButton setTitle:@"签到" forState:UIControlStateNormal];
    [self.checkInButton setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];
    [self.checkInButton setBackgroundColor:[UIColor blueColor]];
    [self.checkInButton addTarget:self action:@selector(checkInButtonClicked) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:self.checkInButton];
}

- (void)checkInButtonClicked {
    // 处理签到逻辑
    NSLog(@"签到成功！");
}

@end

这段代码中，我们创建了一个`CheckInViewController`类，其中包括`titleLabel`和`checkInButton`两个控件。在`viewDidLoad`方法中，我们设置了背景颜色，并添加了标题和签到按钮。当用户点击签到按钮时，我们在`checkInButtonClicked`方法中处理签到逻辑，并在控制台输出签到成功的日志。