NSTimer-秒表 [英] NSTimer - Stopwatch

问题描述

我正在尝试使用HH:MM:SS创建秒表，代码如下:

I've trying to create a stopwatch with HH:MM:SS, code is as follows:

-(IBAction)startTimerButton;
{
    myTimer = [NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(showActivity) userInfo:nil repeats:YES];
}


-(IBAction)stopTimerButton;
{
    [myTimer invalidate];
    myTimer = nil;
}


-(void)showActivity;
{
    int currentTime = [time.text intValue];
    int newTime = currentTime + 1;
    time.text = [NSString stringWithFormat:@"%.2i:%.2i:%.2i", newTime];
}

尽管输出确实会按预期增加1秒，但输出格式为XX:YY:ZZZZZZZZZZ，其中XX是秒.

Although the output does increment by 1 second as expected the format of the output is XX:YY:ZZZZZZZZ , where XX are the seconds.

任何人有什么想法吗?

Anyone any thoughts ??

推荐答案

您的stringWithFormat要求输入3个整数，但您只传递了一个;)

Your stringWithFormat asks for 3 integers but you're only passing in one ;)

这里有一些我以前使用过的代码来做我认为您要尝试做的事情:

Here is some code that I've used before to do what I think you're trying to do :

- (void)populateLabel:(UILabel *)label withTimeInterval:(NSTimeInterval)timeInterval {
    uint seconds = fabs(timeInterval);
    uint minutes = seconds / 60;
    uint hours = minutes / 60;

    seconds -= minutes * 60;
    minutes -= hours * 60;

    [label setText:[NSString stringWithFormat:@"%@%02uh:%02um:%02us", (timeInterval<0?@"-":@""), hours, minutes, seconds]];
}

要与计时器一起使用，请执行以下操作:

to use it with a timer, do this :

    ...
    [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(updateTimer:) userInfo:nil repeats:YES];
    ...

- (void)updateTimer:(NSTimer *)timer {
    currentTime += 1;
    [self populateLabel:myLabel withTimeInterval:time;
}

其中currentTime是您要每秒计数一次的NSTimeInterval.

where currentTime is a NSTimeInterval that you want to count up by one every second.

这篇关于NSTimer-秒表的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！