audio播放在Swift中作为UISlider进展

我已经看到了一些关于在Objective-C中完成这个任务的post，但是我一直无法通过Swift做同样的事情。

具体来说，我不知道如何在下面实现addPeriodicTimeObserverForInterval 。

 var player : AVAudioPlayer! = nil @IBAction func playAudio(sender: AnyObject) { playButton.selected = !(playButton.selected) if playButton.selected { let fileURL = NSURL(string: toPass) player = AVAudioPlayer(contentsOfURL: fileURL, error: nil) player.numberOfLoops = -1 // play indefinitely player.prepareToPlay() player.delegate = self player.play() startTime.text = "\(player.currentTime)" endTime.text = NSString(format: "%.1f", player.duration) } else { player.stop() } 

任何援助将不胜感激。

Answer 1

感谢上面的Dare的build议，这里是我做到这一点的：

 var updater : CADisplayLink! = nil @IBAction func playAudio(sender: AnyObject) { playButton.selected = !(playButton.selected) if playButton.selected { updater = CADisplayLink(target: self, selector: Selector("trackAudio")) updater.frameInterval = 1 updater.addToRunLoop(NSRunLoop.currentRunLoop(), forMode: NSRunLoopCommonModes) let fileURL = NSURL(string: toPass) player = AVAudioPlayer(contentsOfURL: fileURL, error: nil) player.numberOfLoops = -1 // play indefinitely player.prepareToPlay() player.delegate = self player.play() startTime.text = "\(player.currentTime)" theProgressBar.minimumValue = 0 theProgressBar.maximumValue = 100 // Percentage } else { player.stop() } } func trackAudio() { var normalizedTime = Float(player.currentTime * 100.0 / player.duration) theProgressBar.value = normalizedTime } @IBAction func cancelClicked(sender: AnyObject) { player.stop() updater.invalidate() dismissViewControllerAnimated(true, completion: nil) } 

Answer 2

只是要详细说明我以前的评论，这是我如何实现它，它似乎工作得很好。 任何Swift更正都是值得欢迎的，我现在仍然是一个Obj-C的人。

 @IBAction func playAudio(sender: AnyObject) { var playing = false if let currentPlayer = player { playing = player.playing; }else{ return; } if !playing { let filePath = NSBundle.mainBundle().pathForResource("3e6129f2-8d6d-4cf4-a5ec-1b51b6c8e18b", ofType: "wav") if let path = filePath{ let fileURL = NSURL(string: path) player = AVAudioPlayer(contentsOfURL: fileURL, error: nil) player.numberOfLoops = -1 // play indefinitely player.prepareToPlay() player.delegate = self player.play() displayLink = CADisplayLink(target: self, selector: ("updateSliderProgress")) displayLink.addToRunLoop(NSRunLoop.currentRunLoop(), forMode: NSDefaultRunLoopMode!) } } else { player.stop() displayLink.invalidate() } } func updateSliderProgress(){ var progress = player.currentTime / player.duration timeSlider.setValue(Float(progress), animated: false) } 

*我在故事板上设置时间滑块的范围在0到1之间

Answer 3

特别是对于Swift，我能够像这样处理它：

1. 我将scrubSlider的最大值设置为在此方法中加载的音乐文件（.mp3）的持续时间

    override func viewDidLoad() { super.viewDidLoad() do { try player = AVAudioPlayer(contentsOfURL: NSURL(fileURLWithPath: NSBundle.mainBundle().pathForResource("bach", ofType: "mp3")!)) scrubSlider.maximumValue = Float(player.duration) } catch { //Error } _ = NSTimer.scheduledTimerWithTimeInterval(1, target: self, selector: #selector(ViewController.updateScrubSlider), userInfo: nil, repeats: true) } 

2. 我的球员被设置为在由洗涤器的值设置的时间播放音乐。

    @IBAction func scrub(sender: AnyObject) { player.currentTime = NSTimeInterval(scrubSlider.value) }