Custom List view in blackberry

class sampleScreen extends MainScreen implements FieldChangeListener
{
    private CustomListField cu_field[];
    private Bitmap image=null;
    int size=8;
    public sampleScreen() {
        VerticalFieldManager vmanager=new VerticalFieldManager(VERTICAL_SCROLL|VERTICAL_SCROLLBAR){
            protected void sublayout(int maxWidth, int maxHeight) {
               
                super.sublayout(Display.getWidth(),Display.getHeight());
                setExtent(Display.getWidth(),Display.getHeight());
            }
        };
        cu_field=new CustomListField[size];
        for(int i=0;i<size;i++){
            image=Bitmap.getBitmapResource("sample_"+i+".jpg");
            cu_field[i]=new CustomListField("BlackBerry models that had a built-in mobile phone, were the first models that natively ran Java, and transmitted data over the normal 2G cellular network. RIM began to advertise these devices as email-capable mobile phones rather than as 2-way pagers.", image, "jan2011", 100, 100,Color.RED);
            cu_field[i].setChangeListener(this);
            vmanager.add(new SeparatorField());
            vmanager.add(cu_field[i]);
        }
        add(vmanager);
    }

    public void fieldChanged(Field field, int context) {
        // TODO Auto-generated method stub
        for(int i=0;i<size;i++){
            if(field==cu_field[i]){
                final int k=i;
                UiApplication.getUiApplication().invokeLater(new Runnable() {
                    public void run() {
                        Dialog.alert("You click on Item No "+k);
                    }
                });
            }
        }
    }
}

class CustomListField extends HorizontalFieldManager{

    private Bitmap scale_image;
    private int width=0;
    private int height=0;
    private int background_color=0;
    private BitmapField bitmap_field;
    private boolean flag=false;
    public CustomListField(String title, Bitmap image, String date,int image_width,int image_height,int background_color){
        super(NO_HORIZONTAL_SCROLL|USE_ALL_WIDTH);
        this.background_color=background_color;
        width=image_width;
        height=image_width;
        if(image!=null){
            scale_image=new Bitmap(image_width, image_height);
            image.scaleInto(scale_image, Bitmap.FILTER_LANCZOS);
            bitmap_field=new BitmapField(scale_image);
            flag=false;
            bitmap_field.setMargin(5, 5, 5, 5);
            add(bitmap_field);
        }
       
       
        VerticalFieldManager vmanager=new VerticalFieldManager(USE_ALL_WIDTH|Field.FIELD_VCENTER){
            protected void sublayout(int maxWidth, int maxHeight) {
                super.sublayout(Display.getWidth()-width, height);
                setExtent(Display.getWidth()-width, height);
            }
        };
        LabelField title_lbl=new LabelField("Title: "+title,Field.NON_FOCUSABLE|DrawStyle.ELLIPSIS);
        vmanager.add(title_lbl);
       
        LabelField date_lbl=new LabelField("Date: "+date,Field.NON_FOCUSABLE);
        vmanager.add(date_lbl);
       
        Font fon=title_lbl.getFont();
        int title_height=fon.getHeight();
       
        Font font=date_lbl.getFont();
        int date_height=font.getHeight();
        int pad=title_height+date_height;
        title_lbl.setPadding((height-pad)/2, 0, 0, 0);
        add(vmanager);
        add(new NullField(FOCUSABLE));
    }
   
    protected void sublayout(int maxWidth, int maxHeight) {
        super.sublayout(Display.getWidth(), height);
        setExtent(Display.getWidth(), height);
    }
    protected void paint(Graphics graphics) {
        if(flag)
        graphics.setBackgroundColor(background_color);
        graphics.clear();
        super.paint(graphics);
    }
    protected void onFocus(int direction) {
        super.onFocus(direction);
        flag=true;
        invalidate();
    }
    protected void onUnfocus() {
        invalidate();
        flag=false;
    }
    protected boolean navigationClick(int status, int time) {
       
        if(Touchscreen.isSupported()){
            return false;
        }else{
            fieldChangeNotify(1);
            return true;
        }
       
    }
    protected boolean touchEvent(TouchEvent message)
    {
        if (TouchEvent.CLICK == message.getEvent())
        {
           
            FieldChangeListener listener = getChangeListener();
            if (null != listener)
                this.setFocus();
                listener.fieldChanged(this, 1);
        }
        return super.touchEvent(message);
    }
}