A question about j2me game

Question

I want to make a programme with this function:
a small dot in the middle, if I click one button "draw",it will draw the line, if I click the "move", it will move without the line
but now , what I can do is the dot just can move , I don't know how it can draw the line...
Can anyone help me?
Ps: here is the code
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
public class main extends MIDlet implements CommandListener
     Display display;
     MyCanvas myCanvas;
     public main(){
          display = Display.getDisplay(this);
          myCanvas = new MyCanvas();
     public void startApp(){
          myCanvas = new MyCanvas();
          display.setCurrent(myCanvas);
          myCanvas.start();
          myCanvas.setCommandListener(this);
     public void pauseApp(){}
     public void destroyApp(boolean unconditional){}
     public void commandAction(Command c, Displayable d){
          if (c == myCanvas.exitCmd)
               destroyApp(true);
               notifyDestroyed();
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import com.nokia.mid.ui.*;
import java.util.Random;
class MyCanvas extends Canvas implements Runnable
     int gameAction;
     Command exitCmd;
     int status = release;
     int k;
     int getKeyCode;
     final static int press = 1;
     final static int release = 2;
     private CommandListener listener;
     int Width = getWidth();
     int Height = getHeight();
     public int x = getWidth()/2;
     public int y = 0;
     public int x_auto;
     public int y_auto;
     int ok;
     int r;
     Random rnd = new Random();
     Image image;
     public MyCanvas(){
          exitCmd = new Command("Exit",Command.EXIT,1);
          addCommand(exitCmd);
          ok = Math.abs(rnd.nextInt()) % 10;
          r = Math.abs(rnd.nextInt()) % 6;
     public void paint(Graphics g){
          g.setColor(0xff8080);
          g.drawRect(2,2,Width-4,Height-4);
          g.setColor(0x000000);
          g.fillArc(x,y+4,2,2,0,360);
          g.fillArc(x+x_auto,Height-4+y_auto,3,3,0,360);
     public void keyPressed(int keyCode){
          getKeyCode = keyCode;
          status=press;
     public void keyReleased(int keyCode){
          status=release;
     public void run(){
          while (true)
               try{
                    Thread.sleep(30);
                    if (getKeyCode == -1 && status == press && y > 2)
                         y--;
                    if (getKeyCode == -2 && status == press && y < Height - 4)
                         y++;
                    if (getKeyCode == -3 && status == press && x >2)
                         x--;
                    if (getKeyCode == -4 && status == press && x < Width - 4)
                         x++;
                    repaint();
               }catch(Exception ex){}
     public void start(){
          Thread runner = new Thread(this);
          runner.start();
     public void setCommandListener(CommandListener l) {
          super.setCommandListener(l);
          listener = l;

Answer 1

Try making the main loop change x_auto and y_auto rather than x and y. At the moment x_auto and y_auto are never initialised, so they're always 0.