How to draw a line after i load a frame?

Question

its simple to draw a line before i load the frame..
when i try to draw a line after i load the frame, i get a error in the last line of the lauchFrame method..
the error is "java.awt.Graphics is abstract; cannot be instantiated"
import java.awt.*;
class GraphArea extends Panel
    public void paint(Graphics g)
        g.setColor(Color.BLUE);
        g.drawLine(0,0,250,250);
    public void paint(Graphics g,int X1, int X2)
        g.drawLine(0,0,X1,X2);
class Grapherv1 {
  private Frame f;
  private GraphArea drawPanel;
  public Grapherv1() {
    f = new Frame("Drawing Shapes:Lenin");
    drawPanel = new GraphArea();
  public void launchFrame() {
      f.setLayout(new FlowLayout());
      drawPanel.setSize(950,550);
      drawPanel.setBackground(new Color(220,220,220));
      drawPanel.setLayout(null);
     f.setBackground(Color.white);
      f.add(drawPanel);
    f.pack();
    f.setSize(1000, 800);
    f.setVisible(true);
    drawPanel.paint(new Graphics(),100,100);
public static void main(String args[]) throws InterruptedException {
      Grapherv1 gui = new Grapherv1();
    gui.launchFrame();
}please tell me how to call this method ...
public void paint(Graphics g,int X1, int X2)
what argument i should pass for Graphics??
Edited by: Tall-Dude on Dec 3, 2007 4:33 PM
Edited by: Tall-Dude on Dec 3, 2007 4:33 PM

Answer 1

Tall-Dude wrote:
please tell me how to call this method ...
public void paint(Graphics g,int X1, int X2)just past the new x1 and x2 and repaint no need to pass the graphics.
e.g.
import java.awt.*;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
class Grapherv1 {
    private Frame f;
    private GraphArea drawPanel;
    public Grapherv1() {
        f = new Frame("Drawing Shapes:Lenin");
        drawPanel = new GraphArea();
    public void launchFrame() {
        f.addWindowListener(new WindowAdapter() {
            public void windowClosing(WindowEvent e) {
                System.exit(0);
        f.setLayout(new BorderLayout());
        drawPanel.setSize(950,550);
        drawPanel.setBackground(new Color(220,220,220));
        drawPanel.setLayout(null);
        f.setBackground(Color.white);
        f.add(drawPanel);
        f.pack();
        f.setSize(1000, 800);
        f.setVisible(true);
        drawPanel.redraw(300,400);
    public static void main(String args[]) throws InterruptedException {
        Grapherv1 gui = new Grapherv1();
        gui.launchFrame();
    class GraphArea extends Panel {
        int x1, x2;
        public void paint(Graphics g) {
            g.setColor(Color.BLUE);
            g.drawLine(0,0,x1,x2);
        public void redraw(int X1, int X2) {
            x1 = X1;
            x2 = X2;
            repaint();
}