An interface that implements an index-maintenance app extension.
- iOS 9.0+
- macOS 10.11+
- Core Spotlight
CSIndex class defines an interface you use to implement an index-maintenance app extension. An index-maintenance app extension facilitates communication between the on-device index and your app, even when your app isn’t running. For more information about using an app extension, see Using Advanced Features in the Index App Content section of the App Search Programming Guide.