Swift 2 Spritekit: Issue with background music not resuming when the game is unpaused - xcode

Question

First of all I would like to thank anyone in advance for any help I get.
I have searched far and wide across the net and cannot find a solution to my issue. My issue is with an iOS game I am building using the SpriteKit framework. I have added a background song using an SKAudioNode and it works fine initially, but when I pause and play the game within a few seconds, the music does not begin playing again. I have tried lots of things like removing the SKAudioNode when the game is paused and adding it again when the game is resumed, but nothing has worked. I have posted a snippet of my code below keeping it as relevant as possible:
class GameScene: SKScene, SKPhysicsContactDelegate {
var backgroundMusic = SKAudioNode(fileNamed: "bg.mp3")
let pauseImage = SKTexture(imageNamed: "pause.png")
var pauseButton:SKSpriteNode!
let playImage = SKTexture(imageNamed: "play2.png")
var playButton:SKSpriteNode!
override func didMoveToView(view: SKView) {
self.addChild(backgroundMusic)
// create pause button
pauseButton = SKSpriteNode(texture: pauseImage)
pauseButton.position = CGPoint(x: self.size.width - pauseButton.size.width, y: pauseButton.size.height)
pauseButton.zPosition = 1
pauseButton.name = "pauseButton"
self.addChild(pauseButton)
// create play button
playButton = SKSpriteNode(texture: playImage)
playButton.position = CGPoint(x: self.size.width - playButton.size.width, y: -playButton.size.height)
playButton.zPosition = 1
playButton.name = "playButton"
self.addChild(playButton)
}
override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
for touch in touches {
if pauseButton.containsPoint(touch.locationInNode(self)) {
let blockOne = SKAction.runBlock({
self.pauseButton.position.y = - self.pauseButton.size.height
self.playButton.position.y = self.playButton.size.height
})
let blockTwo = SKAction.runBlock({
self.view?.paused = true
})
self.runAction(SKAction.sequence([blockOne, blockTwo]))
}
else if(playButton.containsPoint(touch.locationInNode(self))) {
self.playButton.position.y = -self.playButton.size.height
self.pauseButton.position.y = self.pauseButton.size.height
self.view?.paused = false
}
}
}
}

Answer 1

You'll want to look into using AVAudioPlayer and NSNotificationCenter to pass data around the game.
Start the background audio player in your actual GameViewController class.
It's better to do it this way then use SKAudioNode... That's more for sounds that are like sound effects relating to something that happened in gameplay.
By using AVAudioPlayer, the advantage is when the music is paused it's still cued up to play in it's previous spot.
This is one of the few things that will be running regardless of what's going on. So we put it in the GameViewController.
So here's an example of GameViewController code we'd need to start
import AVFoundation
var bgMusicPlayer:AVAudioPlayer?
Then in the GameViewController we make these functions as such
override func viewDidLoad() {
super.viewDidLoad()
// PlayBackgroundSound , PauseBackgroundSound will be your code to send from other "scenes" to use the audio player //
// NSNotificationCenter to pass data throughout the game //
NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(GameViewController.playBackgroundSound(_:)), name: "PlayBackgroundSound", object: nil)
NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(GameViewController.pauseBackgroundSound), name: "PauseBackgroundSound", object: nil)
}
func playBackgroundSound(notification: NSNotification) {
let name = notification.userInfo!["fileToPlay"] as! String
if (bgSoundPlayer != nil){
bgSoundPlayer!.stop()
bgSoundPlayer = nil
}
if (name != ""){
let fileURL:NSURL = NSBundle.mainBundle().URLForResource(name, withExtension: "mp3")!
do {
bgSoundPlayer = try AVAudioPlayer(contentsOfURL: fileURL)
} catch _{
bgSoundPlayer = nil
}
bgSoundPlayer!.volume = 1
bgSoundPlayer!.numberOfLoops = -1
// -1 will loop it forever //
bgSoundPlayer!.prepareToPlay()
bgSoundPlayer!.play()
}
}
func pauseBackgroundSound() {
if (bgSoundPlayer != nil){
bgSoundPlayer!.pause()
}
}
Then when you want to use the audio player in your pause or resume button functions.
Remember you need to have the player used in each scene.
import AVFoundation.AVAudioSession
override func didMoveToView(view: SKView) {
try! AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryAmbient)
}
Then if you want to pause or play something just use NSNotificationCenter.
// To Pause in a scene use this line of code in the function you need to pause the music
NSNotificationCenter.defaultCenter().postNotificationName("PauseBackgroundSound", object: self)
/// To Play initially or a new song .. use this line of code in the function you need to play the music
NSNotificationCenter.defaultCenter().postNotificationName("PlayBackgroundSound", object: self, userInfo: "FILE NAME OF BACKGROUND MUSIC")