childBoundaryRect property
The _boundaryRect is calculated by adding the boundaryMargin to the size of the child.
Implementation
@protected
Rect get childBoundaryRect {
assert(childKey.currentContext != null);
Size childSize;
if (realChildSize != null) {
childSize = realChildSize!;
} else {
final RenderBox childRenderBox =
childKey.currentContext!.findRenderObject()! as RenderBox;
childSize = childRenderBox.size;
}
Offset offset = Offset.zero;
return offset & childSize;
}