如何检查 NSTimer 是否正在运行？

发布于 2024-10-10 04:59:55 字数 849 浏览 4 评论 0原文

我有一个 IBAction，按下按钮后，它会创建一个计划外的计时器。然后，如果同一个计时器已经启动，//做一些事情，否则启动创建的计时器。这是我到目前为止所得到的：

- (IBAction)button1Press {



 NSMethodSignature *sgn = [self methodSignatureForSelector:@selector(onTick:)];
 NSInvocation *inv = [NSInvocation invocationWithMethodSignature: sgn];
 [inv setTarget: self];
 [inv setSelector:@selector(onTick:)];

 NSTimer *tapTimer = [NSTimer timerWithTimeInterval: 1.0
           invocation:inv 
              repeats:NO];



 if (/*tapTimer is running*/) {//do something
  }else{



  NSRunLoop *runner = [NSRunLoop currentRunLoop];
    [runner addTimer: tapTimer forMode: NSDefaultRunLoopMode];
  }

 }

我的问题是把什么作为条件。如果我输入 tapTimer isValid 或 != nil 那么它总是返回 true，因为 tapTimer 已经被声明了。我不想使计时器无效或为零，因为按钮的主要目的是仅在 1 秒的时间间隔内按下按钮两次时才执行操作。

如果有一种完全不同的方法来做我想做的事情，那么请告诉我！

谢谢负载！

原文

I have an IBAction where upon the button being pressed, it creates an unscheduled timer. Then, if that same timer has already started, //do something, else start the timer which was created.
Here is what I have so far:

- (IBAction)button1Press {



 NSMethodSignature *sgn = [self methodSignatureForSelector:@selector(onTick:)];
 NSInvocation *inv = [NSInvocation invocationWithMethodSignature: sgn];
 [inv setTarget: self];
 [inv setSelector:@selector(onTick:)];

 NSTimer *tapTimer = [NSTimer timerWithTimeInterval: 1.0
           invocation:inv 
              repeats:NO];



 if (/*tapTimer is running*/) {//do something
  }else{



  NSRunLoop *runner = [NSRunLoop currentRunLoop];
    [runner addTimer: tapTimer forMode: NSDefaultRunLoopMode];
  }

 }

My problem is what to put as the condition. If I put tapTimer isValid or != nil then it always returns true, because tapTimer is already declared. I do not want to invalidate or nil out the timer because the main purpose of the button is to only do the action if the button is pressed twice in a time interval of 1 second.

If there is a completely different approach to do what I want then please do tell!

Thanks loads!

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半衬遮猫 2024-10-17 04:59:55

据我所知，到目前为止，我看到您正在尝试检查 tapTimer 是否正在运行。我有一个建议。使用变量来指示 TapTimer 是否正在运行。当您运行计时器时，将此变量更改为 true，当计时器的时间达到 0 并调用您选择的方法时，您在此方法中将此变量更改为 false。

这有帮助吗？

回复收藏 0 原文

一直在等你来 2024-10-17 04:59:55

我建议使用 nil 检查来确定计时器是否正在运行。

...
//Define _tapTimer in .h

if (_tapTimer) {//do something
}
else{
   _tapTimer = [[NSTimer timerWithTimeInterval: 1.0
           invocation:inv 
              repeats:NO] retain];
   NSRunLoop *runner = [NSRunLoop currentRunLoop];
   [runner addTimer: _tapTimer forMode: NSDefaultRunLoopMode];
}

...

-(void)timerFired:(NSTimer*)timer
{
   if(timer == _tapTimer)
   {
      //Handle timerfired
      [_tapTimer release], _tapTimer = nil;
   }
}

I would recommend using a nil check to determine if your timer is running or not.

...
//Define _tapTimer in .h

if (_tapTimer) {//do something
}
else{
   _tapTimer = [[NSTimer timerWithTimeInterval: 1.0
           invocation:inv 
              repeats:NO] retain];
   NSRunLoop *runner = [NSRunLoop currentRunLoop];
   [runner addTimer: _tapTimer forMode: NSDefaultRunLoopMode];
}

...

-(void)timerFired:(NSTimer*)timer
{
   if(timer == _tapTimer)
   {
      //Handle timerfired
      [_tapTimer release], _tapTimer = nil;
   }
}

回复收藏 0 原文

迷路的信 2024-10-17 04:59:55

您可以查询 RunLoop 以了解循环内是否有这样的计时器

CFRunLoopRef loopRef = [[runner currentRunLoop] getCFRunLoop];
Boolean timerAdded = CFRunLoopContainsTimer(loopRef, (CFRunLoopTimerRef)timer ,kCFRunLoopDefaultMode)

if (timerAdded)
{
    ...
}

，但是我还没有测试该代码

You can query the RunLoop to know if there is such a timer inside the loop

CFRunLoopRef loopRef = [[runner currentRunLoop] getCFRunLoop];
Boolean timerAdded = CFRunLoopContainsTimer(loopRef, (CFRunLoopTimerRef)timer ,kCFRunLoopDefaultMode)

if (timerAdded)
{
    ...
}

but, I haven't tested that code yet

回复收藏 0 原文

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