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# resizeSublayers(withOldSize:)

Informs the receiver’s sublayers that the receiver’s size has changed.

```
func resizeSublayers(withOldSize size: CGSize)
```

## Parameters

`size`

The previous size of the current layer.

## Discussion

When the [`autoresizingMask`](/documentation/QuartzCore/CALayer/autoresizingMask) property is used for resizing and the bounds of this layer change, the layer calls this method. The default implementation calls the [`resize(withOldSuperlayerSize:)`](/documentation/QuartzCore/CALayer/resize(withOldSuperlayerSize:)) method of each sublayer to let it know its superlayer’s bounds changed. You should not need to call or override this method directly.

---

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