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# NSSplitView.WillResizeSubviewsMessage

```
struct WillResizeSubviewsMessage
```

## Topics

### Initializers

[`init(splitView: NSSplitView, dividerIndex: Int?, userResize: Bool?)`](/documentation/AppKit/NSSplitView/WillResizeSubviewsMessage/init(splitView:dividerIndex:userResize:))

### Instance Properties

[`var dividerIndex: Int?`](/documentation/AppKit/NSSplitView/WillResizeSubviewsMessage/dividerIndex)

[`var splitView: NSSplitView`](/documentation/AppKit/NSSplitView/WillResizeSubviewsMessage/splitView)

[`var userResize: Bool`](/documentation/AppKit/NSSplitView/WillResizeSubviewsMessage/userResize)

## Relationships

### Conforms To

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

[`MainActorMessage`](/documentation/Foundation/NotificationCenter/MainActorMessage)

---

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