I am making an audio player in my iOS project.
I setup the play(audioOfUrl:URL, for times:Int)method by passing the name of the url and how many times the audio file will be play as following:
func play(audioOfUrl:URL, for times:Int) {
let urlPath = audioOfUrl
loopsLeftOver = times
do {
let audio = try AVAudioPlayer.init(contentsOf: urlPath)
audioPlayer = audio
audio.play()
audio.numberOfLoops = times - 1
} catch let error {
print(error.localizedDescription)
}
}
there will be a pause() and resume() as well, What I need to do is keep track of how many loops the audio player leftover.
For example, if I call the play method like this:
play(audioOfUrl:audioUrl, for times:5)
I need to keep eyes on the times leftover as the audio player running.
I try to use the AVAudioPlayerDelegate method, but it is not working, how to keep eyes on the audio.numberOfLoops? Thanks in advance.
You can subscribe for AVPlayerItemDidPlayToEndTime notification and count how many times the handler of this notification has been called.
NotificationCenter.default.addObserver(self, selector:#selector(playerItemDidReachEnd(_:)),
name: NSNotification.Name.AVPlayerItemDidPlayToEndTime,
object: audioPlayer.currentItem)
Related
I have a problem in my SpriteKit game where audio using playSoundFileNamed(_ soundFile:, waitForCompletion:) will not play after the app is interrupted by a phone call. (I also use SKAudioNodes in my app which aren't affected but I really really really want to be able to use the SKAction playSoundFileNamed as well.)
Here's the gameScene.swift file from a stripped down SpriteKit game template which reproduces the problem. You just need to add an audio file to the project and call it "note"
I've attached the code that should reside in appDelegate to a toggle on/off button to simulate the phone call interruption. That code 1) Stops AudioEngine then deactivates AVAudioSession - (normally in applicationWillResignActive) ... and 2) Activates AVAudioSession then Starts AudioEngine - (normally in applicationDidBecomeActive)
The error:
AVAudioSession.mm:1079:-[AVAudioSession setActive:withOptions:error:]: Deactivating an audio session that has running I/O. All I/O should be stopped or paused prior to deactivating the audio session.
This occurs when attempting to deactivate the audio session but only after a sound has been played at least once.
to reproduce:
1) Run the app
2) toggle the engine off and on a few times. No error will occur.
3) Tap the playSoundFileNamed button 1 or more times to play the sound.
4) Wait for sound to stop
5) Wait some more to be sure
6) Tap Toggle Audio Engine button to stop the audioEngine and deactivate session -
the error occurs.
7) Toggle the engine on and of a few times to see session activated, session deactivated, session activated printed in debug area - i.e. no errors reported.
8) Now with session active and engine running, playSoundFileNamed button will not play the sound anymore.
What am I doing wrong?
import SpriteKit
import AVFoundation
class GameScene: SKScene {
var toggleAudioButton: SKLabelNode?
var playSoundFileButton: SKLabelNode?
var engineIsRunning = true
override func didMove(to view: SKView) {
toggleAudioButton = SKLabelNode(text: "toggle Audio Engine")
toggleAudioButton?.position = CGPoint(x:20, y:100)
toggleAudioButton?.name = "toggleAudioEngine"
toggleAudioButton?.fontSize = 80
addChild(toggleAudioButton!)
playSoundFileButton = SKLabelNode(text: "playSoundFileNamed")
playSoundFileButton?.position = CGPoint(x: (toggleAudioButton?.frame.midX)!, y: (toggleAudioButton?.frame.midY)!-240)
playSoundFileButton?.name = "playSoundFileNamed"
playSoundFileButton?.fontSize = 80
addChild(playSoundFileButton!)
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
if let touch = touches.first {
let location = touch.location(in: self)
let nodes = self.nodes(at: location)
for spriteNode in nodes {
if spriteNode.name == "toggleAudioEngine" {
if engineIsRunning { // 1 stop engine, 2 deactivate session
scene?.audioEngine.stop() // 1
toggleAudioButton!.text = "engine is paused"
engineIsRunning = !engineIsRunning
do{
// this is the line that fails when hit anytime after the playSoundFileButton has played a sound
try AVAudioSession.sharedInstance().setActive(false) // 2
print("session deactivated")
}
catch{
print("DEACTIVATE SESSION FAILED")
}
}
else { // 1 activate session/ 2 start engine
do{
try AVAudioSession.sharedInstance().setActive(true) // 1
print("session activated")
}
catch{
print("couldn't setActive = true")
}
do {
try scene?.audioEngine.start() // 2
toggleAudioButton!.text = "engine is running"
engineIsRunning = !engineIsRunning
}
catch {
//
}
}
}
if spriteNode.name == "playSoundFileNamed" {
self.run(SKAction.playSoundFileNamed("note", waitForCompletion: false))
}
}
}
}
}
Let me save you some time here: playSoundFileNamed sounds wonderful in theory, so wonderful that you might say use it in an app you spent 4 years developing until one day you realize it’s not just totally broken on interruptions but will even crash your app in the most critical of interruptions, your IAP. Don’t do it. I’m still not entirely sure whether SKAudioNode or AVPlayer is the answer, but it may depend on your use case. Just don’t do it.
If you need scientific evidence, create an app and create a for loop that playSoundFileNamed whatever you want in touchesBegan, and see what happens to your memory usage. The method is a leaky piece of garbage.
EDITED FOR OUR FINAL SOLUTION:
We found having a proper number of preloaded instances of AVAudioPlayer in memory with prepareToPlay() was the best method. The SwiftySound audio class uses an on-the-fly generator, but making AVAudioPlayers on the fly created slowdown in animation. We found having a max number of AVAudioPlayers and checking an array for those where isPlaying == false was simplest and best; if one isn't available you don't get sound, similar to what you likely saw with PSFN if you had it playing lots of sounds on top of each other. Overall, we have not found an ideal solution, but this was close for us.
In response to Mike Pandolfini’s advice not to use playSoundFileNamed I’ve converted my code to only use SKAudioNodes.
(and sent the bug report to apple).
I then found that some of these SKAudioNodes don’t play after app interruption either … and I’ve stumbled across a fix.
You need to tell each SKAudioNode to stop() as the app resigns to, or returns from the background - even if they’re not playing.
(I'm now not using any of the code in my first post which stops the audio engine and deactivates the session)
The problem then became how to play the same sound rapidly where it possibly plays over itself. That was what was so good about playSoundFileNamed.
1) The SKAudioNode fix:
Preload your SKAudioNodes i.e.
let sound = SKAudioNode(fileNamed: "super-20")
In didMoveToView add them
sound.autoplayLooped = false
addChild(sound)
Add a willResignActive notification
notificationCenter.addObserver(self, selector:#selector(willResignActive), name:UIApplication.willResignActiveNotification, object: nil)
Then create the selector’s function which stops all audioNodes playing:
#objc func willResignActive() {
for node in self.children {
if NSStringFromClass(type(of: node)) == “SKAudioNode" {
node.run(SKAction.stop())
}
}
}
All SKAudioNodes now play reliably after app interrupt.
2) To replicate playSoundFileNamed’s ability to play the short rapid repeating sounds or longer sounds that may need to play more than once and therefore could overlap, create/preload more than 1 property for each sound and use them like this:
let sound1 = SKAudioNode(fileNamed: "super-20")
let sound2 = SKAudioNode(fileNamed: "super-20")
let sound3 = SKAudioNode(fileNamed: "super-20")
let sound4 = SKAudioNode(fileNamed: "super-20")
var soundArray: [SKAudioNode] = []
var soundCounter: Int = 0
in didMoveToView
soundArray = [sound1, sound2, sound3, sound4]
for sound in soundArray {
sound.autoplayLooped = false
addChild(sound)
}
Create a play function
func playFastSound(from array:[SKAudioNode], with counter:inout Int) {
counter += 1
if counter > array.count-1 {
counter = 0
}
array[counter].run(SKAction.play())
}
To play a sound pass that particular sound's array and its counter to the play function.
playFastSound(from: soundArray, with: &soundCounter)
Question:
In Swift code, apart from using an NSTimer, how can I get animations
to start at exact points during playback of a music file played using AVFoundation?
Background
I have a method that plays a music file using AVFoundation (below). I also have UIView animations that I want to start at exact points during the music file being played.
One way I could achieve this is using an NSTimer, but that has the potential to get out of sync or not be exact enough.
Is there a method that I can tap into AVFoundation accessing the music file's time elapsed (time counter), so when certain points during the music playback arrive, animations start?
Is there an event / notification that AVFoundation triggers that gives a constant stream of time elapsed since the music file has started playing?
For example
At 0:52.50 (52 seconds and 1/2), call startAnimation1(), at 1:20.75 (1 minute, 20 seconds and 3/4), call startAnimation2(), and so on?
switch musicPlayingTimeElapsed {
case 0:52.50:
startAnimation1()
case 1:20.75:
startAnimation2()
default:
()
}
Playing music using AVFoundation
import AVFoundation
var myMusic : AVAudioPlayer?
func playMusic() {
if let musicFile = self.setupAudioPlayerWithFile("fileName", type:"mp3") {
self.myMusic = musicFile
}
myMusic?.play()
}
func setupAudioPlayerWithFile(file:NSString, type:NSString) -> AVAudioPlayer? {
let path = NSBundle.mainBundle().pathForResource(file as String, ofType: type as String)
let url = NSURL.fileURLWithPath(path!)
var audioPlayer:AVAudioPlayer?
do {
try audioPlayer = AVAudioPlayer(contentsOfURL: url)
} catch {
print("AVAudioPlayer not available")
}
return audioPlayer
}
If you use AVPlayer instead of AVAudioPlayer, you can use the (TBH slightly awkward) addBoundaryTimeObserverForTimes method:
let times = [
NSValue(CMTime:CMTimeMake(...)),
NSValue(CMTime:CMTimeMake(...)),
NSValue(CMTime:CMTimeMake(...)),
// etc
];
var observer: AnyObject? = nil // instance variable
self.observer = self.player.addBoundaryTimeObserverForTimes(times, queue: nil) {
switch self.player.currentTime() {
case 0:52.50:
startAnimation1()
case 1:20.75:
startAnimation2()
default:
break
}
}
// call this to stop observer
self.player.removeTimeObserver(self.observer)
The way I solve this is to divide the music up into separate segments beforehand. I then use one of two approaches:
I play the segments one at a time, each in its own audio player. The audio player's delegate is notified when a segment finishes, and so starting the next segment — along with accompanying action — is up to me.
Alternatively, I queue up all the segments onto an AVQueuePlayer. I then use KVO on the queue player's currentItem. Thus, I am notified exactly when we move to a new segment.
You might try using Key Value Observing to observe the duration property of your sound as it plays. When the duration reaches your time thresholds you'd trigger each animation. You'd need to make the time thresholds match times >= the trigger time, since you will likely not get a perfect match with your desired time.
I don't know how well that would work however. First, I'm not sure if the sound player's duration is KVO-compliant.
Next, KVO is somewhat resource-intensive, and if your KVO listener gets called thousands of times a second it might bog things down. It would at least be worth a try.
I use AVAudioPlayer to play a click sound if the user taps on a button.
Because there is a delay between the tap and the sound, I play the sound once in viewDidAppear with volume = 0
I found that if the user taps on the button within a time period the sound plays immediately, but after a certain time there is a delay between the tap and the sound in this case also.
It seems like in the first case the sound comes from cache of the initial play, and in the second case the app has to load the sound again.
Therefore now I play the sound every 2 seconds with volume = 0 and when the user actually taps on the button the sound comes right away.
My question is there a better approach for this?
My goal would be to keep the sound in cache within the whole lifetime of the app.
Thank you,
To avoid audio lag, use the .prepareToPlay() method of AVAudioPlayer.
Apple's Documentation on Prepare To Play
Calling this method preloads buffers and acquires the audio hardware
needed for playback, which minimizes the lag between calling the
play() method and the start of sound output.
If player is declared as an AVAudioPlayer then player.prepareToPlay() can be called to avoid the audio lag. Example code:
struct AudioPlayerManager {
var player: AVAudioPlayer? = AVAudioPlayer()
mutating func setupPlayer(soundName: String, soundType: SoundType) {
if let soundURL = Bundle.main.url(forResource: soundName, withExtension: soundType.rawValue) {
do {
player = try AVAudioPlayer(contentsOf: soundURL)
player?.prepareToPlay()
}
catch {
print(error.localizedDescription)
}
} else {
print("Sound file was missing, name is misspelled or wrong case.")
}
}
Then play() can be called with minimal lag:
player?.play()
If you save the pointer to AVAudioPlayer then your sound remains in memory and no other lag will occur.
First delay is caused by sound loading, so your 1st playback in viewDidAppear is right.
I need to change my code from AVAudioPlayer to AVPlayer because it supports rewind and AVAudioPlayer doesn't. Im having trouble with these four lines of code that seeks the audio thats playing using a slider. Here is the code I have:
func changeAudioTime() {
//musicPlayer is declared as AVAudioPlayer and I want to change it to AVPlayer and I named the variable player
musicPlayer.prepareToPlay()
musicPlayer.currentTime = NSTimeInterval(slider.value)
musicPlayer.numberOfLoops = -1
slider.value = Float(musicPlayer.currentTime)
}
For setting the time in both the case you can use this:
self.player.seekToTime(CMTimeMake(Int64(slider.value),1))
slider.value = Float(CMTimeGetSeconds(self.player.currentTime()))
For looping you may try like this, as there is no direct method of loop, till you want to repeat you may set flag/observer and repeat the song if repeat is off you can don't execute observer/seek
NSNotificationCenter.defaultCenter().addObserver(self,
selector: "playerItemDidReachEnd:",name: AVPlayerItemDidPlayToEndTimeNotification,
object: self.player.currentItem)
func playerItemDidReachEnd(notification: NSNotification) {
self.player.seekToTime(kCMTimeZero)
self.player.play()
}
I have been streaming music from remote source using AVPlayer. I get URLs, use one to create an AVPlayerItem, which i then associate with my instance of AVPlayer. I add an observer to the item that I associate with the player to observe when the item finishes playing ( AVPlayerItemDidPlayToEndTimeNotification ). When the observer notifies me at the item end, I then create a new AVPlayerItem and do it all over again. This works well in the foreground AND in the background on iOS 9.2.
Problem: Since I have updated to iOS 9.3 this does not work in the background. Here is the relevant code:
var portionToBurffer = Double()
var player = AVPlayer()
func prepareAudioPlayer(songNSURL: NSURL, portionOfSongToBuffer: Double){
self.portionToBuffer = portionOfSongToBuffer
//create AVPlayerItem
let createdItem = AVPlayerItem(URL: songNSURL)
//Associate createdItem with AVPlayer
player = AVPlayer(playerItem: createdItem)
//Add item end observer
NSNotificationCenter.defaultCenter().addObserver(self, selector: "playerItemDidReachEnd:", name: AVPlayerItemDidPlayToEndTimeNotification, object: player.currentItem)
//Use KVO to see how much is loaded
player.currentItem?.addObserver(self, forKeyPath: "loadedTimeRanges", options: .New, context: nil)
}
override func observeValueForKeyPath(keyPath: String?, ofObject object: AnyObject?, change: [String : AnyObject]?, context: UnsafeMutablePointer<Void>) {
if keyPath == "loadedTimeRanges" {
if let loadedRangeAsNSValueArray = player.currentItem?.loadedTimeRanges {
let loadedRangeAsCMTimeRange = loadedRangeAsNSValueArray[0].CMTimeRangeValue
let endPointLoaded = CMTimeRangeGetEnd(loadedRangeAsCMTimeRange)
let secondsLoaded = CMTimeGetSeconds(endPointLoaded)
print("the endPointLoaded is \(secondsLoaded) and the duration is \(CMTimeGetSeconds((player.currentItem?.duration)!))")
if secondsLoaded >= portionToBuffer {
player.currentItem?.removeObserver(self, forKeyPath: "loadedTimeRanges")
player.play()
}
}
}
}
func playerItemDidReachEnd(notification: NSNotification){
recievedItemEndNotification()
}
func recievedItemEndNotification() {
//register background task
bgTasker.registerBackgroundTask()
if session.playlistSongIndex == session.playlistSongTitles.count-1 {
session.playlistSongIndex = 0
} else {
session.playlistSongIndex += 1
}
prepareAudioPlayer(songURL: session.songURLs[session.playlistSongIndex], portionOfSongToBuffer: 30.00)
}
I have set breakpoints to see that player.play() IS being called when in the background. When i print player.rate it reads 0.0. I have checked the property playbackLikelyToKeepUp of the AVPlayerItem and it is true. I have confirmed also that the new URL is successfully used to create the new AVPlayerItem and associated with the AVPlayer when the app is in the background. I have turned audio and airplay background capabilities on and I have even opened up a finite length background task (in code above as bgTasker.registerBackgroundTask). No idea what is going on.
I found THIS but i'm not sure it helps. Any advice would be great, thanks
When the observer notifies me at the item end, I then create a new AVPlayerItem and do it all over again
But the problem is that meanwhile play stops, and the rule is that background playing is permitted only so long as you were playing in the foreground and continue to play in the background.
I would suggest using AVQueuePlayer instead of AVPlayer. This will allow you to enqueue the next item while the current item is still playing — and thus, we may hope, this will count as continuing to play.
I encountered the similar problem, and I searched lots of websites on google, but didn't find the answer.
The Phenomenon
The problem of my app is that when I start play an audio, and turn the app to background, it will finish the playing of the current audio, and when playing the second audio, it will load some data, but then it stopped, if I turn the app to foreground, it will play the audio.
Solution
My solution is to add the following call.
UIApplication.shared.beginReceivingRemoteControlEvents()
So enable background audio capabilities is not enough, we need to begin receiving remote controller events.