如何更改此代码,使其具有HH:MM:SS(小时,分钟,秒,
你能否告诉我是否需要在.h或.m中添加代码,以便我知道哪一个
此刻它会像1,2,3,4等一样上升
嗨,大家好只是为了让你知道我是一个业余的诱饵你会复制和过去所以我知道你的意思谢谢
亲切的问候
保
·H
@interface FirstViewController : UIViewController {
IBOutlet UILabel *time;
NSTimer *myticker;
//declare baseDate
NSDate* baseDate;
}
-(IBAction)stop;
-(IBAction)reset;
@end
的.m
#import "FirstViewController.h"
@implementation FirstViewController
-(IBAction)start {
[myticker invalidate];
baseDate = [NSDate date];
myticker = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(showActivity) userInfo:nil repeats:YES];
}
-(IBAction)stop;{
[myticker invalidate];
myticker = nil;
}
-(IBAction)reset;{
time.text = @"00:00:00";
}
-(void)showActivity {
NSTimeInterval interval = [baseDate timeIntervalSinceNow];
NSUInteger seconds = ABS((int)interval);
NSUInteger minutes = seconds/60;
NSUInteger hours = minutes/60;
time.text = [NSString stringWithFormat:@"%02d:%02d:%02d", hours, minutes%60, seconds%60];
}
答案 0 :(得分:7)
首先,在 FirstViewController.h 中声明 baseDate 变量,如下所示:
@interface FirstViewController : UIViewController {
IBOutlet UILabel *time;
NSTimer *myticker;
//declare baseDate
NSDate* baseDate;
}
然后,在 FirstViewController.m 启动方法中添加baseDate = [NSDate date]
,如下所示:
-(IBAction)start {
[myticker invalidate];
baseDate = [NSDate date];
myticker = [NSTimer scheduledTimerWithTimeInterval:.01 target:self selector:@selector(showActivity) userInfo:nil repeats:YES];
}
之后,将 showActivity 方法更改为:
-(void)showActivity {
NSTimeInterval interval = [baseDate timeIntervalSinceNow];
double intpart;
double fractional = modf(interval, &intpart);
NSUInteger hundredth = ABS((int)(fractional*100));
NSUInteger seconds = ABS((int)interval);
NSUInteger minutes = seconds/60;
NSUInteger hours = minutes/60;
time.text = [NSString stringWithFormat:@"%02d:%02d:%02d:%02d", hours, minutes%60, seconds%60, hundredth];
}
另请注意,您必须更改计时器的间隔值,否则您的标签每秒只会更新一次。