My background music gets played twice (at the same time) - ios

Question

When i launch my app, a background music starts to play. But when i press start and play the game (in another viewcontroller) and then go back to menu (the first view controller) the song starts again but while the same song is still playing (result = hearing it twice at the same time).Very annoying. This is my viewDidLoad function (probably where my problem is). Can someone help me (by explaining or giving code) playing the music only the first time that the view loads ?
override func viewDidLoad() {
super.viewDidLoad()
// get path of audio file
let myFilePathString = NSBundle.mainBundle().pathForResource("Background Music Loop (Free to Use)", ofType: "mp3")
if let myFilePathString = myFilePathString {
let myFilePathURL = NSURL(fileURLWithPath: myFilePathString)
do { try myAudioPlayer = AVAudioPlayer(contentsOfURL: myFilePathURL)
myAudioPlayer.play()
myAudioPlayer.numberOfLoops = -1
}catch{
print("error")
}
}
}

Answer 1

myAudioPlayer.play will simply be called again, since the VC runs the viewDidLoad() method again.
My idea:
declare a variable
var x = false
next step - make a condition on your audio player to play.
if x == false { // your code here }
when triggering the Segue from the other VC try to use the prepareForSegue method.
So on 2nd ViewController
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?)
{
if segue.identifier == "yourIdentifier" {
let destinationController = segue.destinationViewController as! // Controller Name here
destinationController.x = true
}
}
This will set the x to true and the music doesn't run again.

Answer 2

It all depends on the functionality you want.
If you only want the background music to play when the menu view controller is on screen you could make the file name and player variables properties on the view controller and then in viewWillAppear do
Player.play
And then when a user navigates away from the page stop it playing in the viewDidDissappear function.
If you want the music to always play in the background then it might be worth creating your own class for it and providing a sharedInstance on the app delegate so that you can manage a single instance of the player throughout the application.