19.2 · Notification Service and Notification Content extensions

A remote notification can be changed on the device before the user sees it, and its expanded view can be your own UI. Both happen in extensions with very small budgets.

Mental model. The service extension gets a mutable copy and a short deadline. Always call the handler, always with something deliverable.

Changing and showing a notification

Service and content extensions.

1. How do Notification Service and Notification Content extensions work: mutable content, the deadline, attachments, decryption, and what goes wrong? 19.2.1 · L5
   A Notification Service Extension (UNNotificationServiceExtension, the com.apple.usernotifications.service point) lets your app modify a remote notification…

More in Extensions, widgets & intents

• 19.1 · Extension processes, limits, and sharing data with the app
• 19.3 · Share, Action, keyboards, message filtering, web extensions and network extensions
• 19.4 · WidgetKit timelines, families, refresh budgets, interactivity and controls
• 19.5 · App Intents, Shortcuts, Siri and Spotlight
• 19.6 · The watch app model, Watch Connectivity, and complications
• 19.7 · Top Shelf on tvOS, and treating extensions as a product API
• 19.8 · Timeline fallbacks, testing, bundles and rendering modes
• 19.9 · Dependencies, entities and queries, errors, and build-time metadata
• 19.10 · Info.plist, bundle ids, app group containers and shared payloads