Discussion of Activity 6.2 - Constructing a frame using GridLayout

Sample solution

Code for class LayoutDemo:

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

public class LayoutDemo extends JFrame
{
   private JPanel p;
   private JButton top1, top2, top3;
   private JButton middle1, middle2, middle3;
   private JButton bottom1, bottom2, bottom3;

   public LayoutDemo(String title)
   {
      setTitle(title);
      setSize(200,200);
      setLocation(200,200);
      setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);  //see note 2

      // Create the panel.
      p = new JPanel();
      //using four argument constructor as in 5th instruction
      p.setLayout(new GridLayout(3,3,10,10));

      // Create the buttons.
      top1 = new JButton("O");
      top2 = new JButton("X");
      top3 = new JButton("O");
      middle1 = new JButton("O");
      middle2 = new JButton(" ");
      middle3 = new JButton("X");
      bottom1 = new JButton(" ");
      bottom2 = new JButton(" ");
      bottom3 = new JButton("X");

      // Add the buttons to the panel.
      p.add(top1);
      p.add(top2);
      p.add(top3);
      p.add(middle1);
      p.add(middle2);
      p.add(middle3);
      p.add(bottom1);
      p.add(bottom2);
      p.add(bottom3);
 
      // Get the content pane of the frame.
      Container cp = getContentPane();
      // Add the panel to the content pane;
      cp.add(p);
   }
}

Code for class LayoutDemoTest:

public class LayoutDemoTest
{
   public LayoutDemoTest()
   {
   }

   public static void main(String[] args)
   {
      LayoutDemo ld =
      new LayoutDemo("Tic-tac-toe");
      ld.setVisible(true);
   }
}

Notes