NotificationCenter is a legacy framework for building Today-widget extensions that appear in the Notification Center on iOS and macOS. You adopt the NCWidgetProviding protocol in a widget extension and report data freshness through NCUpdateResult, and you use NCWidgetController to manage whether your widget has content to display. The framework also supplies presentation controllers such as NCWidgetListViewController and NCWidgetSearchViewController, along with their NCWidgetListViewDelegate and NCWidgetSearchViewDelegate protocols, for laying out list-based and searchable widget content.
Widget Lifecycle 2
Adopt the providing protocol and report data freshness for a Today-widget extension.
- PrNCWidgetProvidingA protocol you adopt in a widget extension to update content and report data freshness.
- EnNCUpdateResultConstants that indicate whether a widget's content changed after an update.
Widget Content Management 1
Manage whether your widget has content available to display.
- ClNCWidgetControllerAn object that manages whether a Today-widget extension currently has content to display.
List and Search Presentation 2
Lay out list-based and searchable widget content using the supplied view controllers.
- ClNCWidgetListViewControllerA view controller that presents list-based content within a Today-widget extension.
- ClNCWidgetSearchViewControllerA view controller that presents searchable content within a Today-widget extension.
Presentation Delegates 2
Respond to interaction and data requests from the list and search view controllers.
- PrNCWidgetListViewDelegateA protocol for responding to row events and data requests from a widget list view controller.
- PrNCWidgetSearchViewDelegateA protocol for responding to search queries and results from a widget search view controller.