Blackberry Vertical Layout Size and Vertical Scrollbar

VerticalFieldManager myLayout = new VerticalFieldManager
(VerticalFieldManager.FIELD_LEFT |
 VerticalFieldManager.FOCUSABLE | VerticalFieldManager.USE_ALL_WIDTH|
 VerticalFieldManager.VERTICAL_SCROLL|VerticalFieldManager.
 VERTICAL_SCROLLBAR){
 protected void sublayout(int maxWidth, int maxHeight) {
        int setWidth = Display.getwidth -20;
        int setHeight = Display.getHeight -130;
        super.sublayout(setWidth, setHeight);
        }
};