public void setSelected(KWTCheckbox box) {
        if (box != null && box.group != this) {
            return;
        }
        KWTCheckbox oldChoice = this.selected;
        this.selected = box;
        if (oldChoice != null && oldChoice != box && oldChoice.group == this) {
            oldChoice.setSelected(false);
        }
        if (box != null && oldChoice != box && !box.isSelected()) {
            box.setSelected(true);
        }
    }