view method
Implementation
BoxView view(int i)
{
// get children
var children = widget.model.viewableChildren;
// find box model at specified child index
Widget? view;
if (children.length > i) {
view = children.elementAt(i).getView();
if (view is BoxView) return view;
}
// missing view
return BoxView(BoxModel(widget.model, null), (_,__) => const []);
}