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# didBecomeActiveNotification

Posted immediately after the app becomes active.

```
class let didBecomeActiveNotification: NSNotification.Name
```

## Discussion

The notification object is [`shared`](/documentation/AppKit/NSApplication/shared). This notification doesn’t contain a `userInfo` dictionary.

The system posts this notification on the main actor.

To observe this notification using Swift concurrency, use [`NSApplication.DidBecomeActiveMessage`](/documentation/AppKit/NSApplication/DidBecomeActiveMessage).

---

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