we have a more complete mechanism for composite children, see [gtk.widget_class.WidgetClass.setTemplate].
Widget.pushCompositeChild
void pushCompositeChild()Makes all newly-created widgets as composite children until the corresponding [gtk.widget.Widget.popCompositeChild] call.
A composite child is a child that’s an implementation detail of the container it’s inside and should not be visible to people using the container. Composite children aren’t treated differently by GTK+ (but see [gtk.container.Container.foreach_] vs. [gtk.container.Container.forall]), but e.g. GUI builders might want to treat them in a different way.
Deprecated
This API never really worked well and was mostly unused, now