(iOS) 音乐文件停止时的动作

Question

当我打开一个视图时，音乐开始使用 AVFoundation 播放，然后当它结束时，如何在它停止时创建一个动作？所以当音乐文件完成时，我希望 "Pause" 按钮变成 "Play"。我已经知道如何使用 btnPausePlay.setTitle("Pause", forState: UIControlState.Normal) 以编程方式更改文本，但是当音乐停止播放时如何创建函数？

注意：我正在使用 swift

Answer 1

您可以为此使用委托函数，这是您的完整代码：

import UIKit
import AVFoundation

class ViewController: UIViewController, AVAudioPlayerDelegate {

    var player = AVAudioPlayer()

    @IBOutlet weak var musicSlider: UISlider!
    @IBOutlet weak var btnPausePlay: UIButton!

    override func viewDidLoad() {
        super.viewDidLoad()
        musicSlider.value = 0.0
        music()
    }

    func updateMusicSlider(){

        musicSlider.value = Float(player.currentTime)
    }

    @IBAction func sliderAction(sender: AnyObject) {

        player.stop()
        player.currentTime = NSTimeInterval(musicSlider.value)
        player.play()
    }

    func music(){

        var audioPath = NSBundle.mainBundle().pathForResource("1", ofType: "mp3")!
        var error : NSError? = nil
        player = AVAudioPlayer(contentsOfURL: NSURL(string: audioPath), error: &error)
        musicSlider.maximumValue = Float(player.duration)
        var timer = NSTimer.scheduledTimerWithTimeInterval(0.05, target: self, selector: Selector("updateMusicSlider"), userInfo: nil, repeats: true)
        player.delegate = self
        if error == nil {
            player.delegate = self
            player.prepareToPlay()
            player.play()
        }
    }
    //This delegate method will call when your player finish playing. 
    func audioPlayerDidFinishPlaying(player: AVAudioPlayer!, successfully flag: Bool)
    {
        btnPausePlay.setTitle("Play", forState: .Normal)
    }

}

HERE 是您的示例项目以获取更多信息。

(iOS) 音乐文件停止时的动作

(iOS) Action when music file stops

xcode

avfoundation

avaudioplayer

ios

swift