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# preferredSupplementaryColumnWidth

The preferred width, in points, of the supplementary view controller’s content.

```
var preferredSupplementaryColumnWidth: CGFloat { get set }
```

## Discussion

Use this property to specify your preferred width for the supplementary view controller’s view. The default value of this property is [`automaticDimension`](/documentation/UIKit/UISplitViewController/automaticDimension). If you set this property to a value different from [`automaticDimension`](/documentation/UIKit/UISplitViewController/automaticDimension), that value takes precedence over [`preferredSupplementaryColumnWidthFraction`](/documentation/UIKit/UISplitViewController/preferredSupplementaryColumnWidthFraction).

The values in the [`minimumSupplementaryColumnWidth`](/documentation/UIKit/UISplitViewController/minimumSupplementaryColumnWidth) and [`maximumSupplementaryColumnWidth`](/documentation/UIKit/UISplitViewController/maximumSupplementaryColumnWidth) properties constrain the actual width of the supplementary view controller. The split view controller attempts to use the width you specify, but may change this value to accommodate the available space. You can get the actual width for the supplementary view controller’s view from the [`supplementaryColumnWidth`](/documentation/UIKit/UISplitViewController/supplementaryColumnWidth) property.

---

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