Specifies a mode to use to enforce an aspect ratio.
| None | The aspect ratio is not enforced. |
| WidthControlsHeight | Changes the height of the rectangle to match the aspect ratio. |
| HeightControlsWidth | Changes the width of the rectangle to match the aspect ratio. |
| FitInParent | Sizes the rectangle such that it's fully contained within the parent rectangle. |
| EnvelopeParent | Sizes the rectangle such that the parent rectangle is fully contained within. |