How do I perform segue AFTER the sound has stopped playing - ios

Question

I have made a custom LaunchScreen in the Main.Storyboard to make it seem that a sound is actually coming from the LaunchScreen. The sound works fine and the segue to the next view controller as well. The only problem is that the segue happens before the sound has stopped playing. I would like the sound to complete before making the segue. Logically, it should work since the performSegue is directly after the .play(). But it seems that the two happens simultaneously. Here's my code:
super.viewDidLoad()
//PLAY SOUND CLIP//
let musicFile = Bundle.main.path(forResource: "fanfare", ofType: ".mp3")
do {
try musicSound = AVAudioPlayer(contentsOf: URL (fileURLWithPath: musicFile!))
} catch { print("ERROR PLAYING MUSIC")}
musicSound.play() //WORKS
//
DispatchQueue.main.async() {
self.performSegue(withIdentifier: "myLaunchSegue", sender: self) //WORKS
}
I have tried to add:
perform(Selector(("showNavController")), with: self, afterDelay: 3)
where "showNavController" simply is the segue:
func showNavController() {
performSegue(withIdentifier: "myLaunchSegue", sender: nil)
}
but the program crashes with the error "uncaught exception.... ....unrecognized selector sent to instance"
I have also tried to add a boolean to keep the program from progressing until the sound has played, but didn't get it to work. Any ideas?
//////////////////////////
Update:
Trying Russels answer, but have a few questions. Setting AVAudioPlayer as delegate, does that mean setting it next to the class like this:
class MyLaunchViewController: UIViewController, AVAudioPlayer { ...
Also, how do I call the function audioPlayerDidFinishPlaying? Like so:
audioPlayerDidFinishPlaying(musicSound, successfully: true)
I'll post the whole code block. Makes it easier to understand...
import UIKit
import AVFoundation //FOR SOUND
class MyLaunchViewController: UIViewController, AVAudioPlayer {
var musicSound: AVAudioPlayer = AVAudioPlayer() //FOR SOUND
override func viewDidLoad() {
super.viewDidLoad()
//PLAY SOUND CLIP//
let musicFile = Bundle.main.path(forResource: "fanfare", ofType: ".mp3")
do {
try musicSound = AVAudioPlayer(contentsOf: URL (fileURLWithPath: musicFile!))
} catch { print("ERROR PLAYING MUSIC")}
musicSound.play() //WORKS
//
audioPlayerDidFinishPlaying(musicSound, successfully: true)
}
optional func audioPlayerDidFinishPlaying(_ player: AVAudioPlayer, successfully flag: Bool) {
DispatchQueue.main.async() {
self.performSegue(withIdentifier: "myLaunchSegue", sender: self)
}
}
I get an error when writing AVAudioPlayer in the class (perhaps I misunderstood what I was supposed to do?). It says I have multiple inheritances. Also, it doesn't want me to set the new function as optional, as its only for protocol members. Finally, If I correct the errors and run the program, the next segue runs before the sound has finished playing... :( sad panda.

Answer 1

You need to make your LaunchScreen an AVAudioPlayerDelegate, and then use the audioPlayerDidFinishPlaying callback. Here's all you need in the first controller
import UIKit
import AVFoundation
class ViewController: UIViewController, AVAudioPlayerDelegate
{
var musicSound: AVAudioPlayer?
override func viewDidLoad() {
super.viewDidLoad()
//PLAY SOUND CLIP//
let musicFile = Bundle.main.path(forResource: "sound", ofType: ".wav")
do {
try musicSound = AVAudioPlayer(contentsOf: URL (fileURLWithPath: musicFile!))
} catch { print("ERROR PLAYING MUSIC")}
musicSound?.delegate = self
musicSound!.play() //WORKS
print("Next line after play")
}
func audioPlayerDidFinishPlaying(_ player: AVAudioPlayer, successfully flag: Bool) {
DispatchQueue.main.async() {
print("audioPlayerDidFinishPlaying")
self.performSegue(withIdentifier: "myLaunchSegue", sender: self)
}
}
}
You can get more details here https://developer.apple.com/documentation/avfoundation/avaudioplayerdelegate/1389160-audioplayerdidfinishplaying