NSExtensionContext.WillResignActiveMessage
A message the system sends when the extension’s host app moves from the active to the inactive state.
Declaration
struct WillResignActiveMessageOverview
Your extension can use this message to adjust the extension’s activity when it becomes inactive. For example, you might use this message to save any unsaved data to prevent it from being lost.
Observe this message with the identifier willResignActive, or specify its type directly to the addObserver(of:for:using:) method. The Subject of this message type is NSExtensionContext.
This message interoperates with the notification NSExtensionHostWillResignActive. The system notifies observers of the message when the NotificationCenter posts the notification. Similarly, the system notifies observers of the notification when it posts the message.