Implementing repaint() to panel after mouseclick

[Victor Mota]

I am a beginner with this Java GUI (comp sci has taught only basic basic things) and I am trying to get mouseclick to work on a panel but when the mouseclick method is called the drawings I make in them are not repainted to the panel. How would I go about doing this? And I do know that the mousepressed is working since I have tried doing a System.close(0) with it and it has worked, it is just the graphics that are screwy. Please help!

  import java.awt.*;
import hsa.Console;
import BreezyGUI.*;
import javax.swing.*;
import java.awt.event.*;

public class Main extends JFrame
{
    public static void main (String[] args)
  {
    //c = new Console (20, 40, 25);
    
    //x is 600, y is 520
    
    JFrame frame = new TicMoTacToe();
    frame.setSize (600, 520);
    //frame.setLocationRelativeTo (null);
    //TicMoTacToe.d.drawChecker();


    //drawO(1,3);
    //drawX (3,1);
    
    // Place your program here.  'c' is the output console
  } // main method
  
}  

  import java.awt.*;
import hsa.Console;
import BreezyGUI.*;
import javax.swing.*;
import java.awt.event.*;

public class TicMoTacToe extends JFrame implements MouseListener
{
  
  JPanel content;
  
  static Console c; // The output console 
  
  JLabel area;
  public static Drawing d = new Drawing();
  
  public TicMoTacToe() 
  {    

    
    this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    this.setVisible(true);
    this.setBackground (Color.white);
    this.pack();   // does layout of components.
    
    content = new JPanel ();
    this.setContentPane(content);
    content.addMouseListener(this);
    d.setSize(600,520);
    d.setVisible(true);
    d.setOpaque(true);
    
    content.add(d);
    //d.addMouseListener(this);
    //d.setSize(600,520);
    //d.setVisible(true);
    //d.setOpaque(true);
    //d.drawO(1,1);
    //this.setContentPane (d);
   
    

    
    
  }
  void pass (int x, int y)
  {
    d.drawO(1,1);
    
  }
  public void mousePressed(MouseEvent e) {   
    
    d.drawChecker();
    d.repaint();
    
  }
  
  public void mouseReleased(MouseEvent e) {
 
  }
  
  public void mouseEntered(MouseEvent e) {
    pass(3,3);
  }
  
  public void mouseExited(MouseEvent e) {
    pass(3,3);
  }
  
  public void mouseClicked(MouseEvent e) {
    pass(3,3);
  }
 
  
  protected int mouseX, mouseY;

  
} 


  

  import java.awt.*;
import javax.swing.*;

class Drawing extends JPanel {
  Graphics g;
  @Override public void paintComponent(Graphics pC) {
    super.paintComponent(pC);    // paints background
    pC.setColor (Color.black);
    g = pC;
    
    
  }
  public void drawChecker ()
  {
    //Draws checker
    for (int count = 0; count <= 6; count++)//first vertical line
    {
      g.drawLine(197+count, 0, 197+count, 520);
    }
    for (int count = 0; count <= 6; count++)//second vertical line
    {
      g.drawLine(397+count, 0, 397+count, 520);
    }
    for (int count = 0; count <= 6; count++)//first horizontal line
    {
      g.drawLine(0, 170 +count, 600, 170 +count);
    }
    for (int count = 0; count <= 6; count++)//second horizontal line
    {
      g.drawLine(0, 343 +count, 600, 343 +count);
    }
    repaint();
  }
}  

[pete stein]

Your problem is that to do proper graphics programming in Swing you (we) first have to shed many assumptions. For instance you should not extract a JPanel's Graphic object as you're doing it and assuming that it will persist because it won't. Read a tutorial or two on Swing graphics and you'll see that you should do all of your drawing in the JPanel's paintComponent method only and use the Graphics object that has been passed as a parameter (but don't try to save it as again it won't persist).

e.g.,

   @Override
   public void paintComponent(Graphics g) {
      System.out.println(getSize());
      super.paintComponent(g); 
      g.setColor(Color.black);
      Graphics2D g2 = (Graphics2D) g;
      Stroke oldStroke = g2.getStroke();
      g2.setStroke(new BasicStroke(8)); // to make thick lines
      
      Dimension size = getSize();
      
      g.drawLine(size.width/3, 0, size.width/3, size.height);
      g.drawLine(2*size.width/3, 0, 2*size.width/3, size.height);
      g.drawLine(0, size.height/3, size.width, size.height/3);
      g.drawLine(0, 2*size.height/3, size.width, 2*size.height/3);
      
      g2.setStroke(oldStroke);
   }

Some other things you might want to check out: I'd set the preferred size (not the size -- your current JPanel is size 10 x 10) of the drawing panel, and leave the JFrame size alone -- let it decide what is the best size based on its components. I'd pack and set the JFrame visible after adding components not before. I wouldn't set the background color of the JFrame but rather its components or its content pane.

Much luck.