延迟后执行一个方法

I want to execute a method -recognized 2 seconds after the -touchesEnded method has finished execution. However, If the user touches something within these 2 seconds, the method must not be executed. A timer must again be set up to wait for 2 seconds after the -touchesEnded method has been executed again the next time. And so on... Hope this question is clear enough. If not, do let me know.

我想在-touchesEnded方法完成执行后2秒执行一个方法 - 识别。但是，如果用户在这2秒内触摸了某些内容，则不得执行该方法。在下次再次执行-touchesEnded方法后，必须再次设置计时器等待2秒。等等......希望这个问题足够清楚。如果没有，请告诉我。

3 个解决方案

#1

You need to use an NSTimer to coordinate this. When the event you want to start the timer is triggered use scheduledTimerWithTimeInterval:target:selector:userInfo:repeats: to schedule a function call in two seconds.

您需要使用NSTimer来协调它。当您想要启动计时器的事件被触发时，使用scheduledTimerWithTimeInterval：target：selector：userInfo：重复：在两秒钟内调度函数调用。

Use a Boolean variable that is global to your view controller to prevent the timer from getting set in between.

使用视图控制器的全局布尔变量，以防止在其间设置计时器。

Here is a rough idea:

这是一个粗略的想法：

BOOL shouldRespondToTouch = YES;

- (void)touchesEnded {
    [NSTimer scheduledTimerWithTimeInterval:2.0 target:self selector:@selector(doAction) userInfo:nil repeats:NO];
    shouldRespondToTouch = NO;
}

- (void)doAction {
    shouldRespondToTouch = YES;
    // Do stuff here
}

#2

    -(void) touchesEnded {
    [NSTimer scheduledTimerWithInterval: 1.0 target:self selector:@selector(targetMethod:) userInfo:nil repeats: YES];

    }

    //define the targetmethod
    -(void) targetMethod: NSTimer * theTimer
 {
    NSLog(@\"Me is here at 1 minute delay\");
    }

#3

Turns out, that it is really simple.

事实证明，这很简单。

Create an ivar in view.h

在view.h中创建一个ivar

NSDate *startDate;

Add the following to these methods in view.m

在view.m中将以下方法添加到这些方法中

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
self->startDate = [NSDate date];
NSLog(@"%@", startDate);
}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
if (self->startDate) {
        NSTimeInterval ti = [[NSDate date] timeIntervalSinceDate:self->startDate];
        NSLog(@"Time: %f", ti);
        if (ti >= 2 ) {
            NSLog(@"Yes, greater than 2 seconds !");
        }
    }
}

Works like a charm.

奇迹般有效。

#1