Question

I am designing a GUI to emulate a Nurikabe game (description here). I basically have two JPanels, and when one of buttons in the control panel (panel 2) is clicked, I want to change the buttons in the game panel (panel 1).

Panel 1 has 36 buttons, either non-clickable buttons displaying numbers or clickable blank buttons, all contained in a GridLayout.

Panel 2 has three buttons, new puzzle, check puzzle, and reset current puzzle.

The problem I am running into is that I cannot figure out how to change Panel 1’s buttons when either the reset or new puzzle button is clicked without having to display a new window.

Is there a way to do this?

Code: (I have removed the check puzzle and reset puzzle buttons)

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

public class SSCCE extends JFrame {

private static final int[][] puzzle1 = { { 0, 1 }, { 1, 0 } };
private static final int[][] puzzle2 = { { 1, 0 }, { 0, 1 } };

private int[][] puzzle;

private JFrame frame;
private JPanel gridPanel;
private JPanel buttonPanel;

public SSCCE(final int puzzleNum) {
    frame = new JFrame("SSCCE");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    if (puzzleNum == 1) {
        puzzle = puzzle1;
    } else {
        puzzle = puzzle2;
    }

    setLayout(new BorderLayout());

    gridPanel = new JPanel(new GridLayout(2, 2));
    for (int i = 0; i < this.puzzle.length; i++) {
        for (int j = 0; j < this.puzzle[0].length; j++) {
            JButton button;
            if (this.puzzle[i][j] > 0) {
                button = new JButton("" + this.puzzle[i][j]);
            } else {
                button = new JButton();
                button.addActionListener(new ActionListener() {
                    public void actionPerformed(ActionEvent event) {
                        JButton temp = ((JButton) event.getSource());
                        if (temp.getBackground() == Color.BLACK) {
                            // if the button is black, set it to white
                            temp.setBackground(Color.WHITE);
                        } else if (temp.getBackground() == Color.WHITE) {
                            // if the button is white, set it to black
                            temp.setBackground(Color.BLACK);
                        }
                    }
                });
            }
            button.setBorderPainted(false);
            button.setContentAreaFilled(false);
            button.setOpaque(true);
            button.setBackground(Color.WHITE);

            gridPanel.add(button);
        }
    }

    buttonPanel = new JPanel(new FlowLayout(FlowLayout.CENTER));

    JButton changePuzzle = new JButton("New Puzzle");
    changePuzzle.addActionListener(new ActionListener() {
        public void actionPerformed(ActionEvent event) {
            loadNewPuzzle(puzzleNum);
        }
    });

    buttonPanel.add(changePuzzle);

    add(gridPanel, BorderLayout.CENTER);
    add(buttonPanel, BorderLayout.SOUTH);
    setTitle("SSCCE");
    setLocation(100, 100);
    pack();
    setSize(150, 150);
}

private void loadNewPuzzle(int puzzleNum) {
    if (puzzleNum == 1) {
        puzzleNum = 2;
    } else {
        puzzleNum = 1;
    }

    // I know this is the wrong way to do it, but I'm not sure how
    // to do it.
    SSCCE newGame = new SSCCE(puzzleNum);
    newGame.setVisible(true);
}

public static void main(String[] args) {
    SSCCE game = new SSCCE(1);
    game.setVisible(true);
}
}

Answer 1

// suppose you want to make button 2 visible and hide button 1 in panel 1 on clicking 
//   button  3 from panel 2, you can do something like this:

// add everything you want to display or not in respective panels.
// Then the contents that you dont want to get displayed,make them invisible by calling
   setVisible(false).
// Then for button 3 in panel 2, write actionlistener like this:
     button3.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent ae) {
              // make the visible buttons invisible by using setVisible(false);
              // make the invisible buttons visible by using setVisible(true);
          }
     });