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# didChangeNotification

Posted whenever a font collection is changed.

```
class let didChangeNotification: NSNotification.Name
```

## Discussion

The notification’s object is the font collection that was affected. The notification’s `userInfo` dictionary contains information about the the collection change containing the keys defined in [`NSFontCollection.UserInfoKey`](/documentation/AppKit/NSFontCollection/UserInfoKey) and the corresponding values.

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

---

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