MusicKit

Search the Apple Music catalog, manage playback with ApplicationMusicPlayer, check subscriptions, and publish Now Playing metadata via MPNowPlayingInfoCenter and MPRemoteCommandCenter.

Contents

• Setup
• Workflow
• Authorization
• Catalog Search
• Subscription Checks
• Playback with ApplicationMusicPlayer
• Queue Management
• Now Playing Info
• Remote Command Center
• Common Mistakes
• Review Checklist
• References

Workflow

1. Verify the MusicKit App Service, bundle identifier, purpose string, and background-audio mode before debugging code.
2. Request authorization, then model every non-authorized state explicitly.
3. Search or load catalog content and check MusicSubscription.current before queueing playback.
4. Choose ApplicationMusicPlayer for app-scoped playback; wire Now Playing and remote commands only when the app owns those surfaces.
5. Test authorized, denied, unsubscribed, offline, queue failure, interruption, and track-change states. Fix the smallest failing layer, restore the fixture, and rerun the same state matrix.

Setup

Project Configuration

1. Enable the MusicKit App Service for the app's explicit bundle ID in the Apple Developer portal so MusicKit can generate developer tokens automatically.
2. Add NSAppleMusicUsageDescription to Info.plist explaining why the app accesses the user's media library.
3. For background playback, add the audio background mode to UIBackgroundModes.

Imports

import MusicKit       // Catalog, auth, playback
import MediaPlayer    // MPRemoteCommandCenter, MPNowPlayingInfoCenter

Authorization