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# itemDidExpandNotification

Posted whenever an item is expanded in an `NSOutlineView` object.

```
class let itemDidExpandNotification: NSNotification.Name
```

## Discussion

The notification object is the `NSOutlineView` object in which an item was expanded. The `userInfo` dictionary contains the following information:

|Key          |Value                               |
|-------------|------------------------------------|
|`@"NSObject"`|The item that was expanded (an `id`)|

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

---

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