GridBagLayout 为什么第三列更大？

Question

我试图使按钮的宽度相等，并且它们的总和它们之间的宽度应该与它们上面的JTextField一样宽。法典：window.setLayout(new GridBagLayout());GridBagConstraints gb = new GridBagConstraints();gb.gridx = 0;gb.gridy = 0;gb.gridwidth = 3;gb.fill = GridBagConstraints.HORIZONTAL;gb.gridwidth = GridBagConstraints.REMAINDER;window.add(text,gb); //adds JTextFieldgb.gridwidth = 1;gb.gridy++;window.add(one,gb); //adds JButtongb.gridx++;window.add(two,gb); //adds JButtongb.gridx++;window.add(three,gb); //adds JButton当我使用时，发生这种情况：gb.gridwidth = GridBagConstriants.RELATIVE;

Answer 1

您可以通过设置按钮来实现此目的。GridBagConstraints.weightx = 1.0

要注意的另一个关键事项是，我已将文本字段和按钮添加到 a 中，然后将其添加到 的内容窗格中。我没有将文本字段和按钮直接添加到内容窗格中。JPanelJPanelJFrame

import javax.swing.*;

import java.awt.*;

public class EqualWidthButtons

{

  public static void main(String[] args)

  {

    JPanel panel = new JPanel();

    panel.setLayout(new GridBagLayout());

    GridBagConstraints gb = new GridBagConstraints();

    gb.gridx = 0;

    gb.gridy = 0;

    gb.gridwidth = 3;

    gb.fill = GridBagConstraints.HORIZONTAL;

    panel.add(new JTextField(20), gb);

    gb.gridwidth = 1;

    gb.gridy++;

    gb.weightx = 1.0; // This is the important line

    panel.add(new JButton("1"), gb);

    gb.gridx++;

    panel.add(new JButton("2"), gb);

    gb.gridx++;

    panel.add(new JButton("3"), gb);

    JFrame frame = new JFrame();

    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    frame.getContentPane().setLayout(new GridBagLayout());

    frame.getContentPane().add(panel, new GridBagConstraints());

    frame.setBounds(300, 200, 400, 300);

    frame.setVisible(true);

  }

}

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