Creating Audio Apps for watchOS
Creating Audio Apps for watchOS
WWDC 2018
Native Controls
Now playing view
- Digital Crown controls volume
- Place in non-scrolling controller
- Automatically switches source
- Application tint color
Volume control
- Controls iPhone or local volume ( Watch )
- Application tint color
Getting Content
WatchConnectivity
The content might already exist on iPhone.
We can just use watchConnectivity and transfer the file directly over to the Watch
- Transfer file API
- Progress
- Sample Link
Which one do we use ?
- URLSession
- User initiated on Apple Watch
- UsewaitsForConnectivityinstead of SCNetworkReachability
- Requests are proxied through iPhone, when in range - WatchConnectivity
- Initiated on iPhone
- No need to request from your server again
Set Expectations
- Instruct your user
- On the magnetic charger
WatchKit
presentMediaPlayerController(with: option: completion: )
- WKAudioFileQueuePlayer
- WKAudioFilePlayerItem
AVFoundation
- AVAudioPlayer
- AVAudioEngine
- Playback
- Background run mode (new)
- Foreground, screen on - Formats supported
- AAC-LC, AAC-ELD, HE-AAC, HE-AACv2, MP3 (decoding only), Opus
Background Playback ( new )
- AVFoundation
- Route picking
- MediaPayer.framework
- Restricted to Bluetooth routes just like Music, Podcasts, and Radio
Local Playback
- Set
routeSharingPolicytolongFormon AVAudioSession - Call new
activate(withOptions: completion: )method on AVAudioSession
- On completion, callplay()
Route Picker
- Apple wireless chip, W1
- Bluetooth headphones
- If user has an active route, the route picker will select that automatically on your behalf
- Takes active W1 route from iPhone (Unless iPhone has more priority )
- If no active routes, route picker will appear
Power
- Only play audio when necessary
- AVAudioEngine
- autoShutdownEnabled on by default
MediaPlayer.framework
- Provide Now Playing information
- Now Playing UI will update
- Handles events
Media remote
- Use MediaPlayer.framework
- Handle commands however you wish
- Sample Link
Audio Experience
- Auto launch
- Frontmost App state
- Notifications
- Shortcuts
Auto Launch
- Auto launch Audio Apps
- Now Playing session on iPhone brings Apple Watch app frontmost
- Stays frontmost for duration of the session
Now Playing session API
- You will know when you’re launched for a Now Playing session on iPhone
- Take your user directly to the view
- Use
handleRemoteNowPlayingActivity()on WKExtensionDelegate
Opt out
- App can opt out
- Do the right thing
- Info.plist key
- Now Playing app will show if you have opted out
Frontmost App State
- WatchConnectivity resumes
- URLSession resumes
- Frontmost notification
- Haptics
- Kept frontmost while playing audio
- User navigates away
- Background playback still occurs - Properly handle background events
- The Life of a watchOS App ( WWDC 2017 )
Notifications
- Content available local notification
- Play option as the primary action
- Configuration step
- What’s New in watchOS ( WWDC 2018 )
Frontmost notifications
func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void)- Play haptic
Shortcuts
- Donate
INMediaPlaybackIntent
- Relevant shortcut API
- Shortcut phrase
