Question

我正在尝试在不使用SpriteKit的情况下在iOS中创建游戏。我被困在及时发挥声音效果。我一直在使用我在网上找到的以下代码，背景音乐效果很好。但是，当我使用的时候＆＃34; playSoundEffect＆＃34;方法它第一次播放然后开始落后并变得不同步。我想这是因为它每次都初始化一个AVAudioPlayer。任何人都知道如何及时播放音效，同时还播放背景音乐？谢谢！

import AVFoundation

public class SKTAudio: NSObject, AVAudioPlayerDelegate {
public var backgroundMusicPlayer: AVAudioPlayer?
public var soundEffectPlayer: AVAudioPlayer?

private var mainLoopFileName:String! {

    let randomSong = Int(arc4random_uniform(3))

    switch randomSong {
    //case 0: return "Test.mp3"
    //case 1: return "Test2.mp3"
    case 0: return "SneakySnitch.mp3"
    case 1: return "FasterDoesIt.mp3"
    case 2: return "MonkeysSpinningMonkeys.mp3"
    default:
        break
    }

    return "SneakySnitch.mp3"
}

public class func sharedInstance() -> SKTAudio {
    return SKTAudioInstance
}

public func playBackgroundMusic() {
    let filename = mainLoopFileName
    let url = NSBundle.mainBundle().URLForResource(filename, withExtension: nil)
    if (url == nil) {
        println("Could not find file: \(filename)")
        return
    }

    var error: NSError? = nil
    backgroundMusicPlayer = AVAudioPlayer(contentsOfURL: url, error: &error)
    if let player = backgroundMusicPlayer {
        player.numberOfLoops = 0
        player.delegate = self
        player.prepareToPlay()
        player.play()
    } else {
        println("Could not create audio player: \(error!)")
    }
}

public func pauseBackgroundMusic() {
    if let player = backgroundMusicPlayer {
        if player.playing {
            player.pause()
        }
    }
}

public func resumeBackgroundMusic() {
    if let player = backgroundMusicPlayer {
        if !player.playing {
            player.play()
        }
    }
}

public func playSoundEffect(filename: String) {
    let url = NSBundle.mainBundle().URLForResource(filename, withExtension: nil)
    if (url == nil) {
        println("Could not find file: \(filename)")
        return
    }

    var error: NSError? = nil
    soundEffectPlayer = AVAudioPlayer(contentsOfURL: url, error: &error)
    if let player = soundEffectPlayer {
        player.numberOfLoops = 0
        player.prepareToPlay()
        player.play()
    } else {
        println("Could not create audio player: \(error!)")
    }
}

// MARK: AVAudioPlayerDelegate
public func audioPlayerDidFinishPlaying(player: AVAudioPlayer!, successfully flag: Bool) {
    println("finished playing \(flag)")

    delay(5.0, {
        self.playBackgroundMusic()
    })
}

public func audioPlayerDecodeErrorDidOccur(player: AVAudioPlayer!, error: NSError!) {
    println("\(error.localizedDescription)")
}

}

Answer 1

您可以使用AVPlayer播放声音文件。保留一个播放器，但在需要播放新声音时将其AVPlayerItem更改为新项目。它可能比每次重新创建播放器更快。

虽然AVAudioPlayer / AVPlayer是最简单的选项，但在播放音频文件时它不会给您最短的延迟或完美的同步。您应该查看Core Audio中的音频队列或音频单元，以获得更准确的声音播放。

Answer 2

问题是你在第一个声音效果完成之前正在播放第二个声音效果。当您将新的AVAudioPlayer设置为soundEffectPlayer变量并且第一个将停止播放时，您将删除对第一个的引用。

如果你不介意失去控制声音音量的可用性，你可以使用它：

var mySound: SystemSoundID = 0
AudioServicesCreateSystemSoundID(url, &mySound)
// Play
AudioServicesPlaySystemSound(mySound)

否则，如果将创建的每个声音添加到数组中，则可以使用AVAudioPlayer，保留引用。然后，您可以通过实施AVAudioPlayer委托来完成声音删除。

func playSound(){
    let path : NSString? = NSBundle.mainBundle().pathForResource("sound", ofType: "wav")!
    let url = NSURL(fileURLWithPath: path!)

    var error : NSError?
    let sound = AVAudioPlayer(contentsOfURL: url, error: &error)
    sound.delegate = self
    sound.volume = 0.5

    self.soundsEffectsArray.addObject(sound)
    sound.prepareToPlay()
    sound.play()
}

func audioPlayerDidFinishPlaying(player: AVAudioPlayer!, successfully flag: Bool) {
    self.soundsEffectsArray.removeObject(player)
}

iOS，swift：毫不拖延地播放背景音乐和声音效果

2 个答案: