【代碼筆記】UILable電子錶顯示，筆記uilable電子錶

【代碼筆記】UILable電子錶顯示，筆記uilable電子錶

一，。

二，代碼。

RootViewController.h

#import <UIKit/UIKit.h>@interface RootViewController : UIViewController{    UILabel *label;    NSDateFormatter  *dateFormatter ;}@end

 

RootViewController.m

#import "RootViewController.h"@interface RootViewController ()@end@implementation RootViewController- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil{    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];    if (self) {        // Custom initialization    }    return self;}- (void)viewDidLoad{    [super viewDidLoad];    // Do any additional setup after loading the view.        //label    label=[[UILabel alloc]initWithFrame:CGRectMake(50, 100, 200, 200)];    label.backgroundColor=[UIColor redColor];    [self.view addSubview:label];        //定時器    [NSTimer scheduledTimerWithTimeInterval:1.0f target:self selector:@selector(updateTime) userInfo:nil repeats:YES];        dateFormatter = [[NSDateFormatter alloc] init];    [dateFormatter setDateFormat:@"HH:mm:ss"];    }- (void)updateTime{    label.text = [dateFormatter stringFromDate:[NSDate date]];}