Creating Tabmenu in j2me - java-me

Question

Is there any way to create a Tab Menu in j2me?
I found a code but I am unable to understand it
In this code there is Tab Menu created which is in Canvas class and then Tab menu is created which is totally done in Canvas or painted. The only part I found difficult to grasp was the void go() method and then
When I try to draw anything above and below this code using paint method, it doesn't work - what's the problem?
Below is the code
// Tab Menu CANVAS class
import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.Graphics;
public class TabMenuCanvas extends Canvas
{
TabMenu menu = null;
public TabMenuCanvas()
{
menu = new TabMenu(
new String[]{"Home", "News", "Community", "Your files", "Credits", "Events", "Blog", "Upload", "Forum Nokia"},
getWidth() - 20
);
}
protected void keyPressed(int key)
{
int gameAction = getGameAction(key);
if(gameAction == Canvas.RIGHT)
{
menu.goRight();
repaint();
}
else if(gameAction == Canvas.LEFT)
{
menu.goLeft();
repaint();
}
}
protected void paint(Graphics g)
{
g.translate(10, 30);
menu.paint(g);
g.translate(- 10, - 30);
}
}
// Tab Menu Class
import javax.microedition.lcdui.Font;
import javax.microedition.lcdui.Graphics;
public class TabMenu
{
int background = 0xffffff;
int bgColor = 0xcccccc;
int bgFocusedColor = 0x0000ff;
int foreColor = 0x000000;
int foreFocusedColor = 0xffffff;
int cornerRadius = 6;
int padding = 2;
int margin = 2;
Font font = Font.getDefaultFont();
int scrollStep = 20;
int selectedTab = 0; //selected tab index
int[] tabsWidth = null; //width of single tabs
int[] tabsLeft = null; //left X coordinate of single tabs
int tabHeight = 0; //height of tabs (equal for all tabs)
String[] tabs = null; //tab labels
int menuWidth = 0; //total menu width
int viewportWidth = 0; //visible viewport width
int viewportX = 0; //current viewport X coordinate
public TabMenu(String[] tabs, int width)
{
this.tabs = tabs;
this.viewportWidth = width;
initialize();
}
void initialize()
{
tabHeight = font.getHeight() + cornerRadius + 2 * padding; //[ same for all tabs]
menuWidth = 0;
tabsWidth = new int[tabs.length];
tabsLeft = new int[tabs.length];
for(int i = 0; i < tabsWidth.length; i++)
{
tabsWidth[i] = font.stringWidth(tabs[i]) + 2 * padding + 2 * cornerRadius;
tabsLeft[i] = menuWidth;
menuWidth += tabsWidth[i];
if(i > 0)
{
menuWidth += margin;
}
}
}
public void goRight()
{
go(+1);
}
public void goLeft()
{
go(-1);
}
private void go(int delta)
{
int newTab = Math.max(0, Math.min(tabs.length - 1, selectedTab + delta));
boolean scroll = true;
if(newTab != selectedTab && isTabVisible(newTab))
{
selectedTab = newTab;
if( (delta > 0 && tabsLeft[selectedTab] + tabsWidth[selectedTab] > viewportX + viewportWidth) ||
(delta < 0 && tabsLeft[selectedTab] < viewportX))
{
scroll = true;
}
else
{
scroll = false;
}
}
if(scroll)
{
viewportX = Math.max(0, Math.min(menuWidth - viewportWidth, viewportX + delta * scrollStep));
}
}
private boolean isTabVisible(int tabIndex)
{
return tabsLeft[tabIndex] < viewportX + viewportWidth &&
tabsLeft[tabIndex] + tabsWidth[tabIndex] >= viewportX;
}
public void paint(Graphics g)
{
int currentX = - viewportX;
g.setClip(0, 0, viewportWidth, tabHeight);
g.setColor(background);
g.fillRect(0, 0, viewportWidth, tabHeight);
for(int i = 0; i < tabs.length; i++)
{
g.setColor(i == selectedTab ? bgFocusedColor : bgColor);
g.fillRoundRect(currentX, 0, tabsWidth[i], tabHeight + cornerRadius, 2 * cornerRadius, 2 * cornerRadius);
g.setColor(i == selectedTab ? foreFocusedColor : foreColor);
g.drawString(tabs[i], currentX + cornerRadius + padding, cornerRadius + padding, Graphics.LEFT | Graphics.TOP);
currentX += tabsWidth[i] + margin;
}
}
}

Answer 1

When I try to draw anything above and below this code using paint method, it doesn't work
what of the paint methods you use to draw above and below? Pay attention that there are two methods named that way - first is in TabMenuCanvas, second is in TabMenu (second method is invoked from TabMenuCanvas#repaint).
whatever you would try to draw in TabMenuCanvas#paint will most likely be overwritten by setClip and fillRect when TabMenu#paint is invoked following repaint request
The only place where one can expect to be able to draw something visible seems to be in TabMenu#paint method, inside the clip area that is set there.

Answer 2

You can use GUI Libraries for J2ME,for example Lightweight User Interface Toolkit (LWUIT),Flemil have "tab menu".You can see list of GUI Libraries here.