---
title: NSSplitViewItem.CollapseBehavior.useConstraints
framework: appkit
role: symbol
role_heading: Case
path: appkit/nssplitviewitem/collapsebehavior-swift.enum/useconstraints
---

# NSSplitViewItem.CollapseBehavior.useConstraints

The item collapses and expands using a constraint animation, with a constraint priority of the item’s holding priority.

## Declaration

```swift
case useConstraints
```

## Discussion

Discussion This collapse behavior may result in a partial internal content resize and window resize, and doesn’t affect whether the window stays onscreen. You can use external constraints to adjust how the animation affects the item, its sibling items, and the window’s size and position.

## See Also

### Constants

- [NSSplitViewItem.CollapseBehavior.default](appkit/nssplitviewitem/collapsebehavior-swift.enum/default.md)
- [NSSplitViewItem.CollapseBehavior.preferResizingSplitViewWithFixedSiblings](appkit/nssplitviewitem/collapsebehavior-swift.enum/preferresizingsplitviewwithfixedsiblings.md)
- [NSSplitViewItem.CollapseBehavior.preferResizingSiblingsWithFixedSplitView](appkit/nssplitviewitem/collapsebehavior-swift.enum/preferresizingsiblingswithfixedsplitview.md)