getChildScrollOffset method
Implementation
Offset getChildScrollOffset(RenderObject child, Offset offset) {
final RenderLayoutParentData? childParentData = child.parentData as RenderLayoutParentData?;
bool isChildFixed = child is RenderBoxModel ? child.renderStyle.position == CSSPositionType.fixed : false;
// Fixed elements always paint original offset
Offset scrollOffset = isChildFixed ? childParentData!.offset : childParentData!.offset + offset;
return scrollOffset;
}