java - 如何使组件跨越 GridBagLayout 中的多个单元格

Question

我必须为学校做这个：

图形用户界面

这是我到目前为止的代码：

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

public class AddressBookGui1 extends JFrame {
public AddressBookGui1(){

    GridBagLayout gbl = new GridBagLayout();
    GridBagConstraints gbc = new GridBagConstraints();
    setLayout(gbl);

    JLabel label;
    JButton button;
    JTextField textField;
    JTextArea textArea = new JTextArea(10, 20);

    gbc.weightx = 1;
    label = new JLabel("text");
    gbc.fill = GridBagConstraints.HORIZONTAL;
    gbc.gridx = 0;
    gbc.gridy = 0;
    add(label ,gbc);

    textField = new JTextField();
    gbc.weightx = 1;
    gbc.fill = GridBagConstraints.HORIZONTAL;
    gbc.gridx = 1;
    gbc.gridy = 0;
    add(textField ,gbc);

    label = new JLabel("text");
    gbc.weightx = 1;
    gbc.fill = GridBagConstraints.HORIZONTAL;
    gbc.gridx = 0;
    gbc.gridy = 1;
    gbc.gridwidth = 1;
    add(label ,gbc);

    textField = new JTextField();
    gbc.weightx = 1;
    gbc.fill = GridBagConstraints.HORIZONTAL;
    gbc.gridx = 1;
    gbc.gridy = 1;
    gbc.gridwidth = 2;
    add(textField, gbc);

    label = new JLabel("text");
    gbc.weightx = 1;
    gbc.fill = GridBagConstraints.HORIZONTAL;
    gbc.gridx = 0;
    gbc.gridy = 2;
    gbc.gridwidth = 1;
    add(label ,gbc);

    textField = new JTextField();
    gbc.weightx = 1;
    gbc.fill = GridBagConstraints.HORIZONTAL;
    gbc.gridx = 1;
    gbc.gridy = 2;
    gbc.gridwidth = 2;
    add(textField, gbc);

    label = new JLabel("text");
    gbc.weightx = 1;
    gbc.anchor = GridBagConstraints.FIRST_LINE_START;
    gbc.fill = GridBagConstraints.HORIZONTAL;
    gbc.gridx = 0;
    gbc.gridy = 3;
    gbc.gridwidth = 1;
    add(label ,gbc);



    gbc.weightx = 1;
    gbc.fill = GridBagConstraints.HORIZONTAL;
    gbc.anchor = GridBagConstraints.CENTER;
    gbc.gridwidth = 2;
    gbc.gridx = 1;
    gbc.gridy = 3;

    add(textArea, gbc);

    gbc.weightx = 1;
    button = new JButton("text");
    gbc.fill = GridBagConstraints.HORIZONTAL;
    gbc.gridwidth = 1;
    gbc.gridx = 0;
    gbc.gridy = 4;
    add(button ,gbc);

    gbc.weightx = 1;
    button = new JButton("text");
    gbc.fill = GridBagConstraints.HORIZONTAL;
    gbc.gridx = 3;
    gbc.gridy = 4;
    add(button ,gbc);



}
public static void main(String[] args){
  AddressBookGui1 frame = new AddressBookGui1();
  frame.setTitle("Address Book");
  frame.setSize(400, 300);
  frame.setLocationRelativeTo(null);
  frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  frame.setVisible(true); 
}

}

这是结果

（我仍然需要处理填充和插入。我已经让它们在一个更简单的程序中工作，所以我想我可以处理这些东西）

我已经尝试过 GridBagLayout Oracle 教程，但我不确定我做错了什么。有人可以帮我让它看起来更像它应该的样子吗？专门使文本字段和文本区域跨越 2 个单元格。

score 10 · Accepted Answer

关于您的代码，我注意到的几件事。

不要使用setSize()JFrame。这将导致异常行为。相反，让框架根据其组件的大小自行调整大小。如果您希望框架更大，请不要调整框架的大小，而是调整其中的组件。如果您真的想调整大小，您可以设置preferredSize 或覆盖组件的 getpreferredsize，因为 GridBagLayout 是尊重组件的首选大小的布局管理器之一。用于pack()删除不必要的空间。
不要扩展 JFrame，让你的 UI 类有一个主面板并在那里添加所有组件。为该面板（例如 getUI()）提供一个 getter，以提取该类的 UI。
每当要将 GridBagConstraints 对象应用到另一个组件时，请始终重新实例化它。这种方式更具可读性。
使用 insets 在组件周围放置填充。
不要对不同的组件重复使用相同的引用；
使用初始线程
这不是标准的，但我发现它在使用时非常有用GridBagLayout，在设置 gbc 的约束时，按字母顺序进行。

为了解决您的问题，这是修改后的代码，其中包含我指出的有关应用的内容。

public class AddressBook {

    private JPanel pnlMain;

    public AddressBook() {
        pnlMain = new JPanel();
        pnlMain.setLayout(new GridBagLayout());
        GridBagConstraints gbc = new GridBagConstraints();

        JLabel lblName = new JLabel("Name");
        gbc.fill = GridBagConstraints.HORIZONTAL;
        gbc.gridx = 0;
        gbc.gridy = 0;
        gbc.insets = new Insets(0, 10, 0, 0);
        gbc.weightx = 1;
        pnlMain.add(lblName, gbc);

        JTextField txtName = new JTextField();
        gbc = new GridBagConstraints();
        gbc.fill = GridBagConstraints.HORIZONTAL;
        gbc.gridwidth = 3;
        gbc.gridx = 1;
        gbc.gridy = 0;
        gbc.insets = new Insets(5, 0, 0, 10);
        gbc.weightx = 1;
        pnlMain.add(txtName, gbc);

        JLabel lblPhone = new JLabel("Phone");
        gbc = new GridBagConstraints();
        gbc.fill = GridBagConstraints.HORIZONTAL;
        gbc.gridwidth = 1;
        gbc.gridx = 0;
        gbc.gridy = 1;
        gbc.insets = new Insets(0, 10, 0, 0);
        gbc.weightx = 1;
        pnlMain.add(lblPhone, gbc);

        JTextField txtPhone = new JTextField();
        gbc = new GridBagConstraints();
        gbc.fill = GridBagConstraints.HORIZONTAL;
        gbc.gridwidth = 3;
        gbc.gridx = 1;
        gbc.gridy = 1;
        gbc.insets = new Insets(5, 0, 0, 10);
        gbc.weightx = 1;
        pnlMain.add(txtPhone, gbc);

        JLabel lblEmail = new JLabel("Email");
        gbc = new GridBagConstraints();
        gbc.fill = GridBagConstraints.HORIZONTAL;
        gbc.gridwidth = 1;
        gbc.gridx = 0;
        gbc.gridy = 2;
        gbc.insets = new Insets(0, 10, 0, 0);
        gbc.weightx = 1;
        pnlMain.add(lblEmail, gbc);

        JTextField txtEmail = new JTextField();
        gbc = new GridBagConstraints();
        gbc.fill = GridBagConstraints.HORIZONTAL;
        gbc.gridwidth = 3;
        gbc.gridx = 1;
        gbc.gridy = 2;
        gbc.weightx = 1;
        gbc.insets = new Insets(5, 0, 0, 10);
        pnlMain.add(txtEmail, gbc);

        JLabel lblAddress = new JLabel("Address");
        gbc = new GridBagConstraints();
        gbc.fill = GridBagConstraints.HORIZONTAL;
        gbc.gridwidth = 1;
        gbc.gridx = 0;
        gbc.gridy = 3;
        gbc.insets = new Insets(0, 10, 0, 0);
        gbc.weightx = 1;
        pnlMain.add(lblAddress, gbc);

        JTextArea txtAreaAddress = new JTextArea(10, 20);
        JScrollPane pane = new JScrollPane(txtAreaAddress);
        gbc = new GridBagConstraints();
        gbc.anchor = GridBagConstraints.NORTH;
        gbc.fill = GridBagConstraints.BOTH;
        gbc.gridwidth = 3;
        gbc.gridx = 1;
        gbc.gridy = 3;
        gbc.insets = new Insets(5, 0, 0, 10);
        gbc.weightx = 1;
        pnlMain.add(pane, gbc);

        JButton btnSave = new JButton("Save");
        gbc = new GridBagConstraints();
        gbc.anchor = GridBagConstraints.WEST;
        gbc.fill = GridBagConstraints.NONE;
        gbc.gridwidth = 1;
        gbc.gridx = 0;
        gbc.gridy = 4;
        gbc.insets = new Insets(10, 10, 10, 0);
        gbc.weightx = 1;
        pnlMain.add(btnSave, gbc);

        JButton btnCancel = new JButton("Cancel");
        gbc = new GridBagConstraints();
        gbc.anchor = GridBagConstraints.EAST;
        gbc.gridwidth = 1;
        gbc.gridx = 3;
        gbc.gridy = 4;
        gbc.insets = new Insets(10, 0, 10, 10);
        gbc.weightx = 1;
        pnlMain.add(btnCancel, gbc);

    }

    public JPanel getUI(){
        return pnlMain;
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                JFrame frame = new JFrame("Address Book");
                frame.getContentPane().add(new AddressBook().getUI());
                frame.setLocationRelativeTo(null);
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.pack();
                frame.setVisible(true);
            }
        });
    }

}

score 8 · Accepted Answer

gbc.gridwidth 是允许组件跨越多列的参数。例如，如果您有 3 列和 4 行，并且您希望标签占据完整的顶行，那么您需要为标签分配第一个单元格。并设置 gbc.gridwidth = 3;

java - 如何使组件跨越 GridBagLayout 中的多个单元格

2 回答 2

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