java - 网格包布局未按我想要的方式显示

Question

所以我有 6 个面板，它们都使用网格布局。我使用 gridbaglayout 将它们放在一起，这是我想要的设计

结果它变得一团糟“第二个”面板变得更远向右第三个面板向左挤压了很多，这是一场灾难。这是我的 gridbag 布局代码

    c.gridx = 0; c.gridy = 0;
    add (first,c); 

    c.gridx = 2; //so that the second panel starts from the center and is divided evenly with the first panel
    add(second,c);

    c.gridx = 0; c.gridy = 1;
    add(third,c);

    c.gridx = 1; 
    add(fourth,c);

    c.gridx = 2;
    add(fifth,c);

    c.gridx = 3;
    add(sixth,c);

感谢任何帮助。

Answer 1

在您编写 c.gridx = 0 和 c.gridy = 0 时，您忘记指定希望此 JPanel 占据多少列。为了指定它，您应该使用 c.gridwidth = 2，它告诉布局此 JPanel 需要两列的空间。

要得到这样的输出:

这是一个小的工作示例:

import java.awt.*;
import javax.swing.*;
// http://stackoverflow.com/questions/10968853/two-jpanels-in-jframe-one-under-other
public class GridBagLayoutExample
{
    // http://stackoverflow.com/questions/10977017/grid-bag-layout-not-displaying-the-way-i-want
    private void displayGUI()
    {
        JFrame frame = new JFrame("GridBagLayout Example");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        JPanel contentPane = new JPanel();
        contentPane.setLayout(new GridBagLayout());

        GridBagConstraints gbc = new GridBagConstraints();
        gbc.anchor = GridBagConstraints.FIRST_LINE_START;
        gbc.fill = GridBagConstraints.BOTH;
        gbc.gridx = 0;
        gbc.gridy = 0;
        gbc.gridwidth = 2;
        gbc.weightx = 0.5;
        gbc.weighty = 0.2;

        JPanel topLeftPanel = new JPanel();
        topLeftPanel.setOpaque(true);
        topLeftPanel.setBackground(Color.DARK_GRAY);
        contentPane.add(topLeftPanel, gbc);

        gbc.gridx = 2;

        JPanel topRightPanel = new JPanel();
        topRightPanel.setOpaque(true);  
        topRightPanel.setBackground(Color.BLUE);
        contentPane.add(topRightPanel, gbc);

        gbc.gridwidth = 1;
        gbc.gridx = 0;
        gbc.gridy = 1;
        gbc.weightx = 0.25;
        gbc.weighty = 0.8;

        JPanel firstPanel = new JPanel();
        firstPanel.setOpaque(true);
        firstPanel.setBackground(Color.RED);
        contentPane.add(firstPanel, gbc);

        gbc.gridx = 1;

        JPanel secondPanel = new JPanel();
        secondPanel.setOpaque(true);
        secondPanel.setBackground(Color.GREEN.darker());
        contentPane.add(secondPanel, gbc);

        gbc.gridx = 2;

        JPanel thirdPanel = new JPanel();
        thirdPanel.setOpaque(true);
        thirdPanel.setBackground(Color.WHITE);
        contentPane.add(thirdPanel, gbc);

        gbc.gridx = 3;

        JPanel fourthPanel = new JPanel();
        fourthPanel.setOpaque(true);
        fourthPanel.setBackground(Color.MAGENTA);
        contentPane.add(fourthPanel, gbc);

        frame.setContentPane(contentPane);
        frame.setSize(200, 300);
        frame.setLocationByPlatform(true);
        frame.setVisible(true);
    }

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