Question

我知道如何启动NSTimer并且我给出了此代码，但现在我想在3或4分钟后停止NSTimer但是我该怎么做

我知道如何给NSTimer但是如何在3分钟后停止需要一些帮助

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# Agent pid 59566
ssh-add -l
# 2048 a0:dd:42:3c:5a:9d:e4:2a:21:52:4e:78:07:6e:c8:4d /Users/you/.ssh/id_rsa (RSA)

Answer 1

节省启动计时器的时间

-(void)updateUIinMainThread:(NSTimer *)timer
{
    NSDate *timeNow = [NSDate date];
    NSTimeInterval timespan = [timeNow timeIntervalSinceDate:savedTime];
    if(timesapn>180)
    {
       [timer invalidate];
    }
}

并且在函数 updateUIinMainThread：将当前时间与保存时间进行比较。如果结果大于180秒，请停止计时器。

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    foreach ($oneimg as $oneimg_new)
    {
        ?>
        <div class="thumbnail">

            <img src="<?php echo HTTP_IMAGES_PATH_UPLOADIMAGE; ?><?php echo $oneimg_new['images']?>"
                 alt=""  class="img-responsive" style="height:180px; width:100%"/>

        </div>
    <?php
    }
?>

Answer 2

宣言：

int totalSeconds;
NSTimer *twoMinTimer;

代码：

- (void)timer {
    totalSeconds--;

    if ( totalSeconds == 0 ) {
        [twoMinTimer invalidate];
        //Timer stops after 2 minute from this you can do your stuff here
    }
}

- (void)viewWillAppear:(BOOL)animated{
    [super viewWillAppear:animated];
    totalSeconds = 120;
    twoMinTimer = [NSTimer scheduledTimerWithTimeInterval:1.0
                                                   target:self
                                                 selector:@selector(timer)
                                                 userInfo:nil
                                                  repeats:YES];
}

希望这有帮助

Answer 3

以下代码可能会对您有所帮助：

步骤1：声明以下实例变量

@interface yourclass：NSObject {

NSTimer* myTimer;
NSDate *initialDate;

}

第2步：在你想要的课程中创建myTimer：

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

第3步：实现callByTimer方法：

- (void)callByTimer{
// get initial date at very first call by myTimer

if (!initialDate)
{
    initialDate = [NSDate date];
}

// get current date
NSDate *currentDate = [NSDate date];

// get seconds between currentdate and initial date
NSTimeInterval secondsBetween = [currentDate timeIntervalSinceDate:initialDate];

// convert seconds into minutes
NSInteger minutes = secondsBetween/60;

// check if minutes is greater than or equal to 3 then invalidate myTimer and assign nil to initialDate variable
if (minutes>=3)
{
    [myTimer invalidate];
    initialDate = nil;
}}

NSTimer每2秒启动和调用一次，3分钟后停止

3 个答案: