Question

我在使用/实现NSTimer代码时遇到了一些麻烦。到目前为止，我有这个：

//Delay function from http://stackoverflow.com/questions/24034544/dispatch-after-gcd-in-swift/24318861#24318861
func delay(delay:Double, closure:()->()) {
    dispatch_after(
        //adds block for execution at a specific time
        dispatch_time(
            //creates a dispatch time relative to default clock
            DISPATCH_TIME_NOW,
            //Indicates that something needs to happen imediately
            Int64(delay * Double(NSEC_PER_SEC))
            //a 64bit decleration that holds the delay time times by the amount of nanoseconds in one seconds, inorder to turn the 'delay' input into seconds format
        ),
        dispatch_get_main_queue(), closure)
}


@IBAction func computerTurn(){

    if(isFirstLevel){levelLabel.text = ("Level 1"); isFirstLevel = false}
    else{ level++ }

    var gameOrderCopy = gameOrder
    var randomNumber = Int(arc4random_uniform(4))
    gameOrder.append(randomNumber)
    var i = 0
    var delayTime = Double(1)

    println(Double(NSEC_PER_SEC))
    for number in self.gameOrder{


        if number == 0{
            delay(delayTime++){self.greenButton.highlighted = true}
            self.delay(delayTime++){
                self.greenButton.highlighted = false
            }
        }

        else if number == 1{
            delay(delayTime++){self.redButton.highlighted = true}
             self.delay(delayTime++){
                self.redButton.highlighted = false
            }

        }

        else if number == 2{
            delay(delayTime++){self.yellowButton.highlighted = true}
             self.delay(delayTime++){
                self.yellowButton.highlighted = false
            }
        }
        else if number == 3{
            delay(delayTime++){self.blueButton.highlighted = true}
             self.delay(delayTime++){
                self.blueButton.highlighted = false
            }
        }
        println(delayTime)


    }
}

我需要做的是替换计时器功能，或者去除它，并像在这里发生的那样做，但使用NSTimer。

由于

Answer 1

在此上下文中，

NSTimer可能有点笨拙，因为它需要使用target-action或NSInvocation。但是，NSTimer与CFRunLoopTimer免费桥接，您可以使用块调用：

func delay(delay:Double, closure:()->()) {
    let fireDate = delay + CFAbsoluteTimeGetCurrent()
    let timer = CFRunLoopTimerCreateWithHandler(kCFAllocatorDefault, fireDate, 0, 0, 0) { _ in
        closure()
    }
    CFRunLoopAddTimer(CFRunLoopGetCurrent(), timer, kCFRunLoopCommonModes)
}

Answer 2

我建议：

设置一些类属性来维护＆＃34;当前＆＃34;数字索引（你从0开始）;
启动重复计时器;
计时器的处理程序将使用索引来确定要更改的按钮，然后执行一个＆＃34;在＆＃34;然后为＆＃34;做一个dispatch_after，然后转回高亮显示＆＃34 ;;

然后，此处理程序将查看索引并确定您是否在列表的末尾。如果是，请取消计时器，然后完成。如果您不在列表的末尾，那么递增＆＃34;当前索引＆＃34;并等待下一个计划的计时器关闭。

将NSTimer实现为代码 - Swift

2 个答案: