SwiftAudio

SwiftAudio is an audio player written in Swift, making it simpler to work with audio playback from streams and files.

Example

To see the audio player in action, run the example project! To run the example project, clone the repo, and run pod install from the Example directory first.

Requirements

iOS 10.0+

Installation

CocoaPods

SwiftAudio is available through CocoaPods. To install it, simply add the following line to your Podfile:

pod 'SwiftAudio', '~> 0.11.2'

Carthage

SwiftAudio supports Carthage. Add this to your Cartfile:

github "jorgenhenrichsen/SwiftAudio" ~> 0.11.2

Then follow the rest of Carthage instructions on adding a framework.

Usage

AudioPlayer

To get started playing some audio:

let player = AudioPlayer()
let audioItem = DefaultAudioItem(audioUrl: "someUrl", sourceType: .stream)
player.load(item: audioItem, playWhenReady: true) // Load the item and start playing when the player is ready.

To listen for events in the AudioPlayer, subscribe to events found in the event property of the AudioPlayer. To subscribe to an event:

class MyCustomViewController: UIViewController {

    let audioPlayer = AudioPlayer()
    
    override func viewDidLoad() {
        super.viewDidLoad()
        audioPlayer.event.stateChange.addListener(self, handleAudioPlayerStateChange)
    }
    
    func handleAudioPlayerStateChange(state: AudioPlayerState) {
        // Handle the event
    }
}

QueuedAudioPlayer

The QueuedAudioPlayer is a subclass of AudioPlayer that maintains a queue of audio tracks.

let player = QueuedAudioPlayer()
let audioItem = DefaultAudioItem(audioUrl: "someUrl", sourceType: .stream)
player.add(item: audioItem, playWhenReady: true) // Since this is the first item, we can supply playWhenReady: true to immedietaly start playing when the item is loaded.

When a track is done playing, the player will load the next track and update the queue, as long as automaticallyPlayNextSong is true (default).

Navigating the queue

All AudioItems are stored in either previousItems or nextItems, which refers to items that come prior to the currentItem and after, respectively. The queue is navigated with:

player.next() // Increments the queue, and loads the next item.
player.previous() // Decrements the queue, and loads the previous item.
player.jumpToItem(atIndex:) // Jumps to a certain item and loads that item.

Manipulating the queue

 player.removeItem(at:) // Remove a specific item from the queue.
 player.removeUpcomingItems() // Remove all items in nextItems.

Configuring the AudioPlayer

Current options for configuring the AudioPlayer:

• bufferDuration: The amount of seconds to be buffered by the player.
• timeEventFrequency: How often the player should call the delegate with time progress events.
• automaticallyWaitsToMinimizeStalling: Indicates whether the player should automatically delay playback in order to minimize stalling.
• volume
• isMuted
• rate
• audioTimePitchAlgorithm: This value decides the AVAudioTimePitchAlgorithm used for each AudioItem. Implement TimePitching in your AudioItem-subclass to override individually for each AudioItem.

Audio Session

Remember to activate an audio session with an appropriate category for your app. This can be done with AudioSessionController:

try? AudioSessionController.shared.set(category: .playback)
//...
// You should wait with activating the session until you actually start playback of audio.
// This is to avoid interrupting other audio without the need to do it.
try? AudioSessionController.shared.activateSession()

Important: If you want audio to continue playing when the app is inactive, remember to activate background audio: App Settings -> Capabilities -> Background Modes -> Check 'Audio, AirPlay, and Picture in Picture'.

Interruptions

If you are using the AudioSessionController for setting up the audio session, you can use it to handle interruptions too. Implement AudioSessionControllerDelegate and you will be notified by handleInterruption(type: AVAudioSessionInterruptionType). If you are storing progress for playback time on items when the app quits, it can be a good idea to do it on interruptions as well. To disable interruption notifcations set isObservingForInterruptions to false.

Now Playing Info

The AudioPlayer can automatically update nowPlayingInfo for you. This requires automaticallyUpdateNowPlayingInfo to be true (default), and that the AudioItem that is passed in return values for the getters. The AudioPlayer will update: artist, title, album, artwork, elapsed time, duration and rate.

Additional properties for items can be set by accessing the setter of the nowPlayingInforController:

    let player = AudioPlayer()
    player.load(item: someItem)
    player.nowPlayingInfoController.set(keyValue: NowPlayingInfoProperty.isLiveStream(true))

The set(keyValue:) and set(keyValues:) accept both MediaItemProperty and NowPlayingInfoProperty.

The info can be forced to reload/update from the AudioPlayer.

    audioPlayer.loadNowPlayingMetaValues()
    audioPlayer.updateNowPlayingPlaybackValues()

The current info can be cleared with:

    audioPlayer.nowPlayingInfoController.clear()

Remote Commands

To enable remote commands for the player you need to populate the RemoteCommands array for the player:

audioPlayer.remoteCommands = [
    .play,
    .pause,
    .skipForward(intervals: [30]),
    .skipBackward(intervals: [30]),
  ]

These commands will be activated for each AudioItem. If you need some audio items to have different commands, implement RemoteCommandable in a custom AudioItem-subclass. These commands will override the commands found in AudioPlayer.remoteCommands so make sure to supply all commands you need for that particular AudioItem.

Custom handlers for remote commands

To supply custom handlers for your remote commands, just override the handlers contained in the player's RemoteCommandController:

let player = QueuedAudioPlayer()
player.remoteCommandController.handlePlayCommand = { (event) in
    // Handle remote command here.
}

All available overrides can be found by looking at RemoteCommandController.

Start playback from a certain point in time

Make your AudioItem-subclass conform to InitialTiming to be able to start playback from a certain time.

Author

Jørgen Henrichsen

License

SwiftAudio is available under the MIT license. See the LICENSE file for more info.