Horizontal blackberry file manager

i have a horizontal file manager on a screen ...and a vertical field manager inside the horizontal field manager..but the height of the vertical field manager increases and decreases due to a开发者_StackOverflow中文版dding and deleting fields dynamically... and the height of the horizontal file manager changes accordingly which i don't want...i want to fix the height of the horizontal file manager to a specific height..which would be max val for vertical field manager...

how can i do this...

try this code

HorizontalFieldManager hfm = new HorizontalFieldManager(Manager.VERTICAL_SCROLL|Manager.VERTICAL_SCROLLBAR){
                    protected void sublayout(int maxWidth, int maxHeight) {
                        maxHeight = specificHeight;
                        super.sublayout(maxWidth, maxHeight);
                    }
                };