如何在Swift中将播放按钮切换为暂停按钮?

working on my first stopwatch app.

我的第一个秒表程序。

I currently have a play button, pause button, and stop button.

我目前有一个播放按钮，暂停按钮和停止按钮。

I'd like to combine the play and pause button so that they switch back and forth.

我想合并播放和暂停按钮，以便他们来回切换。

My code looks like this:

我的代码是这样的:

var timer = NSTimer()

var count = 0

func updateTime() {

    count++

    time.text = "\(count)"


}

@IBAction func pauseButton(sender: AnyObject) {

    timer.invalidate()

}

@IBOutlet weak var time: UILabel!

@IBAction func stopButton(sender: AnyObject) {

    timer.invalidate()

    count = 0

    time.text = "0"

}

@IBAction func playButton(sender: AnyObject) {

    timer = NSTimer.scheduledTimerWithTimeInterval(1, target: self, selector: Selector("updateTime"), userInfo: nil, repeats: true)


}

Any help is appreciated.

任何帮助都是感激。

3 个解决方案

#1

Try adding booleans. See my code below.

尝试添加布尔值。请参见下面的代码。

 @IBOutlet weak var label: UILabel!

    var time = NSTimer()
    var count = 0

    var running = false

    func result (){

        count++
        label.text = String(count)
        println(count)

    }

    @IBAction func playpause(sender: AnyObject) {

        if running == false {

            time = NSTimer.scheduledTimerWithTimeInterval(1, target: self, selector: Selector("result"), userInfo: nil, repeats: true)

            running = true }

        else {

            time.invalidate()

            running = false

        }



    }

Hope this helps!

希望这可以帮助!

#2

You'll have a variable bound to the button, something like this:

将变量绑定到按钮上，如下所示:

@IBOutlet var thePlayPauseButton : UIButton!

This button will be linked with some action:

这个按钮将会链接一些动作:

@IBAction func togglePlayPauseButton (button: UIButton) {
  // If we are 'paused', then play:
  if button.titleLabel!.text == "Pause" {
    button.titleLabel!.text = "Play"
    // do actual play ...
   timer = NSTimer.scheduledTimerWithTimeInterval (1, 
       target: self, 
       selector: Selector("updateTime"), 
       userInfo: nil, 
       repeats: true)
  }
  else if button.titleLabel!.text == "Play" {
    button.titleLabel!.text = "Pause"
    // do actual pause ...
    timer.invalidate()
  }
  else { /* error */ }
}

Of course, structurally you can use a switch//case and you can perform the toggle behavior by calling your preexisting pause and play methods.

当然，在结构上，您可以使用switch//case，并可以通过调用现有的pause和play方法来执行切换行为。

#3

I know this post is somewhat dated, but I was working with the same problem and I came up with a slightly different answer and wanted to share it to help others. Here is what I came up with in toggling the pause and play buttons.

我知道这篇文章有点过时，但我正在处理同样的问题，我想出了一个稍微不同的答案，想要分享它来帮助别人。这是我在切换暂停和播放按钮时想到的。

class ViewController: UIViewController {

var time = NSTimer()
var seconds = 0
var running = false

func timer() {
    seconds++
    timeLabel.text = "\(seconds)"
}

func playing() {
    time = NSTimer.scheduledTimerWithTimeInterval(1, target: self, selector: Selector("timer"), userInfo: nil, repeats: true)
    running = true
}

func pausing() {
    time.invalidate()
    running = false
}

@IBOutlet weak var timeLabel: UILabel!

@IBAction func stopButton(sender: AnyObject) {
    time.invalidate()
    seconds = 0
    timeLabel.text = "0"
}
@IBAction func pausePlayToggleButton(sender: AnyObject) {
    if running == false {
        return playing()
    } else {
        return pausing()
    }
}

I had both a pause and play button and I essentially took their effects and placed them in functions and used them as return values for a single button.

我有一个暂停和播放按钮，我把它们的效果放在函数中，并把它们作为单个按钮的返回值。

#1