GridBagLayout 网格化不起作用

我正在尝试创建以下 GUI：

但我制作的 GUI 是：

我的网格是什么样的：

image: 网格布局 https://i.stack.imgur.com/Wpzna.png

我不明白为什么我会得到这个输出，因为我已经绘制了一个图表来帮助代码并且它似乎可行。

addComp 方法将输入组件添加到输入面板的给定 (x, y) 位置以及给定组件宽度和高度。

Code:

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

public class GUIError extends JFrame {

    //initialise all the components
    JPanel mainPanel = new JPanel();
    JTextField txtDisplay = new JTextField();
    JButton btnA = new JButton("A");
    JButton btnB = new JButton("B");
    JButton btnC = new JButton("C");
    JButton btnD = new JButton("D");
    JButton btnE = new JButton("E");
    JButton btnF = new JButton("F");
    JButton btnWA = new JButton("WA");
    JButton btnWB = new JButton("WB");
    JButton btnWC = new JButton("WC");
    JButton btnWD = new JButton("WD");

    private void addComp(JPanel panel, JComponent comp, int xPos, int yPos, int compWidth, int compHeight) {

        GridBagConstraints gridConstraints = new GridBagConstraints();

        gridConstraints.gridx = xPos;
        gridConstraints.gridy = yPos;
        gridConstraints.gridwidth = compWidth;
        gridConstraints.gridheight = compHeight;
        gridConstraints.weightx = 0.5;
        gridConstraints.weighty = 0.5;
        gridConstraints.insets = new Insets(5, 5, 5, 5);
        gridConstraints.anchor = GridBagConstraints.CENTER;
        gridConstraints.fill = GridBagConstraints.BOTH;

        panel.add(comp, gridConstraints);

    }


    public static void main(String[] args) {
        try {
            for (UIManager.LookAndFeelInfo info : UIManager.getInstalledLookAndFeels()) {
                if ("Nimbus".equals(info.getName())) {
                    UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        }
        catch (Exception e) { }

        SwingUtilities.invokeLater(new Runnable() {

            public void run() {

                // create frame
                JFrame frame = new JFrame("Calculator");
                frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
                frame.setLocationRelativeTo(null);
                Container c = frame.getContentPane();

                // create GUI within frame              
                new GUIError(c);

                // finish frame definition
                frame.pack();
                frame.setResizable(false);
                frame.setVisible(true);

            }

        });
    }

    public GUIError(Container cont) {

        cont.setPreferredSize(new Dimension(610, 250));

        // parent panel containes every other panel
        mainPanel.setLayout(new GridBagLayout());

        // text display
        txtDisplay.setEditable(false);
        addComp(mainPanel, txtDisplay, 0, 0, 12, 2); // width 16, height 2


        addComp(mainPanel, btnA, 0, 2, 2, 1);
        addComp(mainPanel, btnB, 2, 2, 2, 1);
        addComp(mainPanel, btnC, 4, 2, 2, 1);
        addComp(mainPanel, btnD, 6, 2, 2, 1);
        addComp(mainPanel, btnE, 8, 2, 2, 1);
        addComp(mainPanel, btnF, 10, 2, 2, 1);
        addComp(mainPanel, btnWA, 0, 3, 3, 1);
        addComp(mainPanel, btnWB, 3, 3, 3, 1);
        addComp(mainPanel, btnWC, 6, 3, 3, 1);
        addComp(mainPanel, btnWD, 9, 3, 3, 1);

        cont.add(mainPanel);
    }
}

It can easily be achieved by using GridBagLayout as seen in this example presented below. You simply need to take two JPanel one each for each ROW. Both using GridBagLayout, and add components to the first row, with weightx = 0.16 since each JButton is suppose to take this much area, and for the second row weightx = 0.25 since, this is the area occupied by each JButton along the X direction

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

public class GridBagExample {
    private static final int SIZE = 10;
    private JButton[] buttons;
    private GridBagConstraints gbc;

    public GridBagExample() {
        buttons = new JButton[SIZE];
        gbc = new GridBagConstraints();
        gbc.insets = new Insets(5, 5, 5, 5);
    }

    private void createAndDisplayGUI() {
        JFrame frame = new JFrame("Grid Game");
        frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);

        JPanel contentPane = new JPanel();
        contentPane.setLayout(new GridLayout(2, 1, 5, 5));
        contentPane.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));

        JPanel topPanel = new JPanel();
        JTextField textField = new JTextField(10);
        //topPanel.add(textField);

        JPanel buttonPanel = new JPanel(new GridLayout(2, 1, 5, 5));
        JPanel headerPanel = new JPanel(new GridBagLayout());
        buttons[0] = new JButton("A");
        addComp(headerPanel, buttons[0], 0, 0, 0.16, 1.0, 1, 1, GridBagConstraints.BOTH);        
        buttons[1] = new JButton("B");
        addComp(headerPanel, buttons[1], 1, 0, 0.16, 1.0, 1, 1, GridBagConstraints.BOTH);
        buttons[2] = new JButton("C");
        addComp(headerPanel, buttons[2], 2, 0, 0.16, 1.0, 1, 1, GridBagConstraints.BOTH);
        buttons[3] = new JButton("D");
        addComp(headerPanel, buttons[3], 3, 0, 0.16, 1.0, 1, 1, GridBagConstraints.BOTH);
        buttons[4] = new JButton("E");
        addComp(headerPanel, buttons[4], 4, 0, 0.16, 1.0, 1, 1, GridBagConstraints.BOTH);
        buttons[5] = new JButton("F");
        addComp(headerPanel, buttons[5], 5, 0, 0.16, 1.0, 1, 1, GridBagConstraints.BOTH);

        JPanel footerPanel = new JPanel(new GridBagLayout());
        buttons[6] = new JButton("WA");
        addComp(footerPanel, buttons[6], 0, 0, 0.25, 1.0, 1, 1, GridBagConstraints.BOTH);
        buttons[7] = new JButton("WB");
        addComp(footerPanel, buttons[7], 1, 0, 0.25, 1.0, 1, 1, GridBagConstraints.BOTH);
        buttons[8] = new JButton("WC");
        addComp(footerPanel, buttons[8], 2, 0, 0.25, 1.0, 1, 1, GridBagConstraints.BOTH);
        buttons[9] = new JButton("WD");
        addComp(footerPanel, buttons[9], 3, 0, 0.25, 1.0, 1, 1, GridBagConstraints.BOTH);
        buttonPanel.add(headerPanel);
        buttonPanel.add(footerPanel);

        contentPane.add(textField);
        contentPane.add(buttonPanel);

        frame.setContentPane(contentPane);
        frame.pack();
        frame.setLocationByPlatform(true);
        frame.setVisible(true);
    }

    private void addComp(JPanel panel, JComponent comp, int x, int y,
                                    double wx, double wy, int gw, int gh, int fill) {
        gbc.gridx = x;
        gbc.gridy = y;
        gbc.weightx = wx;
        gbc.weighty = wy;
        gbc.gridwidth = gw;
        gbc.gridheight = gh;
        gbc.fill = fill;

        panel.add(comp, gbc);
    }

    public static void main(String... args) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                new GridBagExample().createAndDisplayGUI();
            }
        });
    }
}

OUTPUT: 网格布局：

可以通过以下方式实现相同的输出GridLayout, if GridBagLayout在这种情况下不是必需的，如下面的示例所示：

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

public class GridBagExample {
    private static final int SIZE = 10;
    private JButton[] buttons;

    public GridBagExample() {
        buttons = new JButton[SIZE];
    }

    private void createAndDisplayGUI() {
        JFrame frame = new JFrame("Grid Game");
        frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);

        JPanel contentPane = new JPanel();
        contentPane.setLayout(new GridLayout(2, 1, 5, 5));
        contentPane.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));

        JPanel topPanel = new JPanel();
        JTextArea tArea = new JTextArea(5, 30);
        JScrollPane scroller = new JScrollPane();
        scroller.setViewportView(tArea);
        topPanel.add(scroller);

        JPanel buttonPanel = new JPanel(new GridLayout(2, 1, 5, 5));
        JPanel headerPanel = new JPanel(new GridLayout(1, 0, 5, 5));
        buttons[0] = new JButton("A");
        headerPanel.add(buttons[0]);
        buttons[1] = new JButton("B");
        headerPanel.add(buttons[1]);
        buttons[2] = new JButton("C");
        headerPanel.add(buttons[2]);
        buttons[3] = new JButton("D");
        headerPanel.add(buttons[3]);
        buttons[4] = new JButton("E");
        headerPanel.add(buttons[4]);
        buttons[5] = new JButton("F");
        headerPanel.add(buttons[5]);
        JPanel footerPanel = new JPanel(new GridLayout(1, 0, 5, 5));
        buttons[6] = new JButton("WA");
        footerPanel.add(buttons[6]);
        buttons[7] = new JButton("WB");
        footerPanel.add(buttons[7]);
        buttons[8] = new JButton("WC");
        footerPanel.add(buttons[8]);
        buttons[9] = new JButton("WD");
        footerPanel.add(buttons[9]);
        buttonPanel.add(headerPanel);
        buttonPanel.add(footerPanel);

        contentPane.add(topPanel);
        contentPane.add(buttonPanel);

        frame.setContentPane(contentPane);
        frame.pack();
        frame.setLocationByPlatform(true);
        frame.setVisible(true);
    }

    public static void main(String... args) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                new GridBagExample().createAndDisplayGUI();
            }
        });
    }
}

OUTPUT: GRIDLAYOUT: