I have a RootElement with Sections. One section has RadioElements. How do I change the BackgroundView on the sub section?

Something like this doesn't work because the sub view isn't yet created.:

        rootGroups = new RootElement ("Ideas", rdoGroup) {
           new RootElement ("Baha'i") {
                new Section (){
                    new RadioElement ("Peace"),
                    new RadioElement ("Unity"),
                    new RadioElement ("Science")    
                }
            }
        };

???
rootGroups.TableView.BackgroundColor = ...;