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# needsDisplayOnBoundsChange

A Boolean indicating whether the layer contents must be updated when its bounds rectangle changes.

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

## Discussion

When this property is set to <doc://com.apple.documentation/documentation/Swift/true>, the layer automatically calls its [`setNeedsDisplay()`](/documentation/QuartzCore/CALayer/setNeedsDisplay()) method whenever its [`bounds`](/documentation/QuartzCore/CALayer/bounds) property changes. The default value of this property is <doc://com.apple.documentation/documentation/Swift/false>.

---

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