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  "identifier" : "/documentation/AppKit/NSSplitViewItem/CollapseBehavior-swift.enum",
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  "title" : "NSSplitViewItem.CollapseBehavior"
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# NSSplitViewItem.CollapseBehavior

Constants that describe the split view item’s collapsing behavior.

```
enum CollapseBehavior
```

## Topics

### Constants

[`NSSplitViewItemCollapseBehaviorDefault`](/documentation/AppKit/NSSplitViewItem/CollapseBehavior-swift.enum/default)

The item uses the default collapsing behavior.

[`NSSplitViewItemCollapseBehaviorPreferResizingSplitViewWithFixedSiblings`](/documentation/AppKit/NSSplitViewItem/CollapseBehavior-swift.enum/preferResizingSplitViewWithFixedSiblings)

The item’s preference is to keep the other panes at their current size and position onscreen, potentially growing or shrinking the window in the direction to best preserve that.

[`NSSplitViewItemCollapseBehaviorPreferResizingSiblingsWithFixedSplitView`](/documentation/AppKit/NSSplitViewItem/CollapseBehavior-swift.enum/preferResizingSiblingsWithFixedSplitView)

The item’s preference is to resize the other split panes.

[`NSSplitViewItemCollapseBehaviorUseConstraints`](/documentation/AppKit/NSSplitViewItem/CollapseBehavior-swift.enum/useConstraints)

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

## Relationships

### Conforms To

[`Hashable`](/documentation/Swift/Hashable)

[`BitwiseCopyable`](/documentation/Swift/BitwiseCopyable)

[`Equatable`](/documentation/Swift/Equatable)

[`RawRepresentable`](/documentation/Swift/RawRepresentable)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`Sendable`](/documentation/Swift/Sendable)

---

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