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# outlineView(_:shouldExpandItem:)

Returns a Boolean value that indicates whether the outline view should expand a given item.

```
@MainActor optional func outlineView(_ outlineView: NSOutlineView, shouldExpandItem item: Any) -> Bool
```

## Parameters

`outlineView`

The outline view that sent the message.

`item`

The item that should expand.

## Return Value

<doc://com.apple.documentation/documentation/Swift/true> to permit `outlineView` to expand `item`, <doc://com.apple.documentation/documentation/Swift/false> to deny permission.

## Discussion

The delegate can implement this method to disallow expanding of specific items.

## See Also

[Outline View](/documentation/AppKit/outline-view)

Display a list-based interface for hierarchical data, where each level of hierarchy is indented from the previous one.

[Drag and Drop](/documentation/AppKit/drag-and-drop)

Support the direct manipulation of your app’s content using drag and drop.


---

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