---
title: extendsBoundary
framework: appkit
role: symbol
role_heading: Instance Property
path: appkit/nscollectionlayoutboundarysupplementaryitem/extendsboundary
---

# extendsBoundary

A Boolean value that indicates whether a boundary supplementary item extends the content area of the section or layout it’s attached to.

## Declaration

```swift
var extendsBoundary: Bool { get set }
```

## Discussion

Discussion The default value of this property is true.

## See Also

### Specifying position

- [offset](appkit/nscollectionlayoutboundarysupplementaryitem/offset.md)
- [alignment](appkit/nscollectionlayoutboundarysupplementaryitem/alignment.md)