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# autoresizesOutlineColumn

A Boolean value that indicates whether the outline view resizes its outline column when the user expands or collapses items.

```
var autoresizesOutlineColumn: Bool { get set }
```

## Discussion

The outline column contains the cells with the expansion symbols and is generally the first column. The default value of this property is <doc://com.apple.documentation/documentation/Swift/true>, which causes the outline column to be resized.

The outline column is resized based on how many indentation levels are exposed or hidden. For example, if expanding a row exposes a single indentation level, the outline column width is increased by one [`indentationPerLevel`](/documentation/AppKit/NSOutlineView/indentationPerLevel).

---

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