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POJAVA SWING: Unable to change text of JTextField
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copied!<p>I am working on a program to generate and solve sudoku puzzles in java using a swing gui. I am having a problem where I use the .setText() method on a JTextField but the text is not updated.</p> <p>Here is my code:</p> <p>main class:</p> <pre><code>package sudoku; public class SudokuSolver { public static void main(String[] args) { GUI gui = new GUI(); gui.setVisible(true); } } </code></pre> <p>GUI class:</p> <pre><code>package sudoku; import java.awt.BorderLayout; import java.awt.EventQueue; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.border.EmptyBorder; import javax.swing.JButton; import java.awt.Window.Type; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; public class GUI extends JFrame implements ActionListener { private JPanel contentPane; private Puzzle puzzle = new Puzzle(); private Board board = new Board(); private int[][] puzz = new int[9][9]; // GUI Constructor public GUI() { // set up window setResizable(false); setTitle("Sudoku Solver"); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setBounds(100, 100, 300, 300); contentPane = new JPanel(); contentPane.setBorder(new EmptyBorder(5, 5, 5, 5)); contentPane.setLayout(new BorderLayout(0, 0)); setContentPane(contentPane); // set up button panel JPanel buttons = new JPanel(); contentPane.add(buttons, BorderLayout.SOUTH); // set up generate button JButton genButton = new JButton("Generate"); genButton.setMnemonic('g'); buttons.add(genButton); genButton.addActionListener(this); // set up solve button JButton solveButton = new JButton("Solve"); solveButton.setMnemonic('s'); buttons.add(solveButton); solveButton.addActionListener(this); // set up board contentPane.add(board, BorderLayout.CENTER); } // Button listener public void actionPerformed(ActionEvent e) { String cmd = e.getActionCommand(); if (cmd == "Generate") { // generate puzzle puzz = puzzle.generate(); } else if (cmd == "Solve") { // solve puzzle puzz = puzzle.solve(puzz); } // display puzzle on the board board.fill(puzz); } } </code></pre> <p>Board class:</p> <pre><code>package sudoku; import java.awt.Color; import java.awt.GridLayout; import javax.swing.BorderFactory; import javax.swing.JPanel; public class Board extends JPanel { // 9x9 board sections private BoardSection nw = new BoardSection(); private BoardSection n = new BoardSection(); private BoardSection ne = new BoardSection(); private BoardSection w = new BoardSection(); private BoardSection c = new BoardSection(); private BoardSection e = new BoardSection(); private BoardSection sw = new BoardSection(); private BoardSection s = new BoardSection(); private BoardSection se = new BoardSection(); // array of sections private BoardSection[] sections = { nw, n, ne, w, c, e, sw, s, se }; // Board Constructor public Board() { // 3x3 grid layout setLayout(new GridLayout(3, 3)); // border setBorder(BorderFactory.createLineBorder(Color.BLACK, 2)); // add board sections to board for (int i = 0; i < sections.length; i++) { sections[i] = new BoardSection(); add(sections[i]); } } // fill the board with data public void fill(int[][] data) { // create data sections String[][] nwData = new String[3][3]; String[][] nData = new String[3][3]; String[][] neData = new String[3][3]; String[][] wData = new String[3][3]; String[][] cData = new String[3][3]; String[][] eData = new String[3][3]; String[][] swData = new String[3][3]; String[][] sData = new String[3][3]; String[][] seData = new String[3][3]; // break data into data sections nwData = createSection(data, 0, 0); nData = createSection(data, 3, 0); neData = createSection(data, 6, 0); wData = createSection(data, 0, 3); cData = createSection(data, 3, 3); eData = createSection(data, 6, 3); swData = createSection(data, 0, 6); sData = createSection(data, 3, 6); seData = createSection(data, 6, 6); // fill board section with data section nw.fillSection(nwData); n.fillSection(nData); ne.fillSection(neData); w.fillSection(wData); c.fillSection(cData); e.fillSection(eData); sw.fillSection(swData); s.fillSection(sData); se.fillSection(seData); } // split data into 3x3 section with 0,0 starting at x, y then convert to // string private String[][] createSection(int[][] data, int x, int y) { int[][] intSection = new int[3][3]; String[][] strSection = new String[3][3]; // break into section for (int i = 0; i < 3; i++) { for (int j = 0; j < 3; j++) { intSection[i][j] = data[i + x][j + y]; } } // convert section to string for (int i = 0; i < 3; i++) { for (int j = 0; j < 3; j++) { strSection[i][j] = Integer.toString(intSection[i][j]); } } return strSection; } } </code></pre> <p>BoardSection class:</p> <pre><code>package sudoku; import java.awt.Color; import java.awt.GridLayout; import javax.swing.JPanel; import javax.swing.JTextField; import javax.swing.BorderFactory; public class BoardSection extends JPanel { // each square private JTextField nw = new JTextField(); private JTextField n = new JTextField(); private JTextField ne = new JTextField(); private JTextField w = new JTextField(); private JTextField c = new JTextField(); private JTextField e = new JTextField(); private JTextField sw = new JTextField(); private JTextField s = new JTextField(); private JTextField se = new JTextField(); // array of the squares private JTextField[] fields = new JTextField[] { nw, n, ne, w, c, e, sw, s, se }; // Board Section Constructor public BoardSection() { // 3x3 grid layout setLayout(new GridLayout(3, 3)); // border setBorder(BorderFactory.createLineBorder(Color.BLACK, 1)); // add all fields to the board section for (int i = 0; i < fields.length; i++) { fields[i] = new JTextField(1); fields[i].setHorizontalAlignment(JTextField.CENTER); fields[i].setEditable(false); add(fields[i]); } } // Display the data on the board public void fillSection(String[][] data) { int x = 0; for (int i = 0; i < 3; i++) { for (int j = 0; j < 3; j++) { fields[x].setText(data[i][j]); x++; } } } } </code></pre> <p>I also have another class called Puzzle where there is a generate() and a solve() method that both return int[][]. I don't believe anything in it is relevant to the problem so I'm omitting it for space.</p> <p>The problem is with this line is the BoardSection class:</p> <pre><code>fields[x].setText(data[i][j]); </code></pre> <p>I am not getting any error messages, however it is not updating the text. I tried replacing data[i][j] with "Z" to see if the problem was the data I was passing but it still doesn't work with just a simple string. I did however try putting the following line in the for loop that is inside the BoardSection constructor method and it DID display.</p> <pre><code>fields[i].setText("0"); </code></pre> <p>Can anyone explain why it works in the constructor but not when the fillSection() method is called?</p>

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