Construct a rounded rectangle from its bounding box and the same radii along its horizontal axis and its vertical axis.
Source
RRect.fromRectXY(Rect rect, double radiusX, double radiusY) {
_value
..[0] = rect.left
..[1] = rect.top
..[2] = rect.right
..[3] = rect.bottom
..[4] = radiusX
..[5] = radiusY
..[6] = radiusX
..[7] = radiusY
..[8] = radiusX
..[9] = radiusY
..[10] = radiusX
..[11] = radiusY;
}