NSExtensionContext.WillEnterForegroundMessage
A message the system sends when the extension’s host app begins running in the foreground.
Declaration
struct WillEnterForegroundMessageOverview
Your extension can use this message to restart tasks that it stopped when the app moved to the background.
Observe this message with the identifier willEnterForeground, 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 NSExtensionHostWillEnterForeground. 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.