GridLayout顶部的FlowLayout不起作用

我试图创build一个hang子手游戏，到目前为止它已经很棒了，但布局devise似乎并没有落到位！ 字母表应该在Hangman图片的顶部以FlowLayout顺序结束，底部有“重新启动”，“帮助”，“添加新字”和“退出”button！ 我究竟做错了什么？

 import java.awt.*; import java.awt.event.*; import javax.swing.*; import java.io.*; public class Hangman extends JFrame { int i = 0; static JPanel panel; static JPanel panel2; static JPanel panel3; public Hangman() { JButton[] buttons = new JButton[26]; panel = new JPanel(new FlowLayout()); panel2 = new JPanel(); panel3 = new JPanel(); JButton btnRestart = new JButton("Restart"); btnRestart.addActionListener(new ActionListener(){ public void actionPerformed(ActionEvent e) { } }); JButton btnNewWord = new JButton("Add New Word"); btnNewWord.addActionListener(new ActionListener(){ public void actionPerformed(ActionEvent e) { try { FileWriter fw = new FileWriter("Words.txt", true); PrintWriter pw = new PrintWriter(fw, true); String word = JOptionPane.showInputDialog("Please enter a word: "); pw.println(word); pw.close(); } catch(IOException ie) { System.out.println("Error Thrown" + ie.getMessage()); } } }); JButton btnHelp = new JButton("Help"); btnHelp.addActionListener(new ActionListener(){ public void actionPerformed(ActionEvent e) { String message = "The word to guess is represented by a row " + "of dashes, giving the number of letters and category of " + "the word. \nIf the guessing player suggests a letter " + "which occurs in the word, the other player writes it " + "in all its correct positions. \nIf the suggested " + "letter does not occur in the word, the other player " + "draws one element of the hangman diagram as a tally mark." + "\n" + "\nThe game is over when:" + "\nThe guessing player completes the word, or guesses " + "the whole word correctly" + "\nThe other player completes the diagram"; JOptionPane.showMessageDialog(null,message, "Help",JOptionPane.INFORMATION_MESSAGE); } }); JButton btnExit = new JButton("Exit"); btnExit.addActionListener(new ActionListener(){ public void actionPerformed(ActionEvent e) { System.exit(0); } }); ImageIcon icon = new ImageIcon("D:\\Varsity College\\Prog212Assign1_10-013803\\images\\Hangman1.jpg"); JLabel label = new JLabel(); label.setIcon(icon); String b[]= {"A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z"}; for(i = 0; i < buttons.length; i++) { buttons[i] = new JButton(b[i]); panel.add(buttons[i]); } panel2.add(label); panel3.add(btnRestart); panel3.add(btnNewWord); panel3.add(btnHelp); panel3.add(btnExit); } public static void main(String[] args) { Hangman frame = new Hangman(); frame.add(panel, BorderLayout.NORTH); frame.add(panel2, BorderLayout.CENTER); frame.add(panel3, BorderLayout.SOUTH); frame.pack(); frame.setVisible(true); } } 

Answer 1

这里有几点build议：

• 使用GridLayout作为顶部面板; 在这种情况下，零表示行数由指定的列数和布局中的组件总数决定：

   JPanel north = new JPanel(new GridLayout(0, 9)); 

• 以下是您如何使中心面板具有合理的初始尺寸的大纲; 注意如何绘制相对于当前的大小：

   JPanel center = new JPanel() { private static final int N = 256; private static final String S = "Todo..."; @Override protected void paintComponent(Graphics g) { super.paintComponent(g); int dx = (getWidth() - g.getFontMetrics().stringWidth(S)) / 2; int dy = getHeight() / 2; g.drawString(S, dx, dy); } @Override public Dimension getPreferredSize() { return new Dimension(N, N); } }; 

• 你可以像这样构造你的button名称：

   for (int i = 0; i < 26; i++) { String letter = String.valueOf((char) (i + 'A')); buttons[i] = new JButton(letter); north.add(buttons[i]); } 

• 使您的面板实例variables，并开始事件调度线程 ：

   EventQueue.invokeLater(new Runnable() { @Override public void run() { Hangman frame = new Hangman(); frame.setDefaultCloseOperation(EXIT_ON_CLOSE); frame.add(frame.north, BorderLayout.NORTH); frame.add(frame.center, BorderLayout.CENTER); frame.add(frame.south, BorderLayout.SOUTH); frame.pack(); frame.setLocationByPlatform(true); frame.setVisible(true); } }); 

Answer 2

如果你做了一些研究，这个问题是非常好的logging – 似乎所有的面板（除了CENTER之外）在重新resize时不会被重新计算。 请参阅如何在其JSplitPane中进行此FlowLayout换行？ 和http://www.velocityreviews.com/forums/t608472-wrap-flowlayout.html

但是要真正快速修复，请尝试将main方法更改为…（基本上使用BoxLayout作为主容器）

 public static void main(String[] args) { TempProject frame = new TempProject(); Box mainPanel = Box.createVerticalBox(); frame.setContentPane(mainPanel); mainPanel.add(panel); mainPanel.add(panel2); mainPanel.add(panel3); frame.pack(); frame.setVisible(true); }