'Formstyle for subform edit-rows, using a vertical
formstyle because multiple fields combined with
location-selector are too complex for horizontal
layout.'

def rowstyle(self, form, fields, *args, **kwargs):

    from s3theme import formstyle_foundation as formstyle
    if args:
        col_id = form
        label = fields
        (widget, comment) = args
        hidden = kwargs.get('hidden', False)
        return formstyle(col_id, label, widget, comment, hidden)
    else:
        parent = TD(_colspan=len(fields))
        for (col_id, label, widget, comment) in fields:
            parent.append(formstyle(col_id, label, widget, comment))
        return TR(parent)
