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# init(sidebarWithViewController:)

Creates a split view item that represents a sidebar for the specified view controller.

```
convenience init(sidebarWithViewController viewController: NSViewController)
```

## Discussion

Sidebar items take advantage of the standard system appearance and behavior for sidebars, including:

- The translucent material background
- The ability to collapse and expand on split view size changes
- The ability to overlay at small split view sizes in full-screen mode

Additionally, sidebars use standard system default values for these properties:

- [`canCollapse`](/documentation/AppKit/NSSplitViewItem/canCollapse) and [`isSpringLoaded`](/documentation/AppKit/NSSplitViewItem/isSpringLoaded) are <doc://com.apple.documentation/documentation/Swift/true>
- [`minimumThickness`](/documentation/AppKit/NSSplitViewItem/minimumThickness) and [`maximumThickness`](/documentation/AppKit/NSSplitViewItem/maximumThickness) use the standard minimum and maximum sidebar size
- [`preferredThicknessFraction`](/documentation/AppKit/NSSplitViewItem/preferredThicknessFraction) uses the standard fraction for sidebars (`0.15`)

---

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