Objective c 秒表圈

我正在使用Xcode 4作为单视图应用程序进行停止监视。。不过我有个问题。当毫秒计数时，它们会向内移动。我希望他们达到9，然后在0重新开始。我还希望秒数达到59，然后回到0。 以下是我的viewcontroller.m文件中的代码：

- (IBAction)start{

    myTicker = [NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(showActivity) userInfo:nil repeats:YES];  


    myTicker2 = [NSTimer scheduledTimerWithTimeInterval:.1 target:self selector:@selector(showActivity1) userInfo:nil repeats:YES];

    myTicker3 = [NSTimer scheduledTimerWithTimeInterval:60 target:self selector:@selector(showActivity2) userInfo:nil repeats:YES];


}
- (IBAction)stop{

    [myTicker invalidate];
    [myTicker2 invalidate];
    [myTicker3 invalidate];
}
- (IBAction)reset{

    time.text = @"00";
    time1.text = @"00";
    time2.text = @"00";
}


- (void)showActivity{

    int currentTime = [time.text intValue];
    int newTime = currentTime + 1;
    time.text = [NSString stringWithFormat:@"%d", newTime];

    }



- (void)showActivity1{


    int currentTime1 = [time1.text intValue];
    int newTime1 = currentTime1 + 1;
    time1.text = [NSString stringWithFormat:@"%d", newTime1];


}


- (void)showActivity2{


    int currentTime2 = [time2.text intValue];
    int newTime2 = currentTime2 = 1;
    time2.text = [NSString stringWithFormat:@"%d", newTime2];



}

这是我在.h文件中的代码

    IBOutlet UILabel *time;
    IBOutlet UILabel *time1;
    IBOutlet UILabel *time2;

    NSTimer *myTicker;
    NSTimer *myTicker2;
    NSTimer *myTicker3;
}

- (IBAction)start;
- (IBAction)stop;
- (IBAction)reset;


- (void)showActivity;
- (void)showActivity1;
- (void)showActivity2;

@end

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任何关于如何做到这一点的答案都将不胜感激。谢谢

在您的情况下，我只使用1个计时器（一个计数毫秒）和4个int变量（小时、分钟、秒和毫秒）。然后在计时器上打勾，你就可以测试了

if (milliseconds > 999)
{
    seconds++;
    milliseconds = 0;
}
if (seconds > 59)
{
    minutes++;
    seconds = 0;
}
if (minutes > 59)
{
    hours++;
    minutes = 0;
}

因此，通过这样做，您有一个计时器来管理所有变量。我快速编写了这段代码，所以可能有拼写错误