Size of buttons inside GridBagLayout

Question

I have an 3 * 6 array of JButtons inside a GridBagLayout. But since the text length of each button may vary, each column of buttons has slightly different width. How do I make them have the same width?

Here is the code:

for (int i = 0; i < 3; i++)
{
    for (int j = 0; j < 6; j++)
    {
        buttonConstraints.fill = GridBagConstraints.BOTH;
        buttonConstraints.weightx = 1;
        buttonConstraints.weighty = 1;
        buttonConstraints.gridx = j;
        buttonConstraints.gridy = i;
        buttonPanel.add(buttons[i * 6 + j], buttonConstraints);
    }
}

Thanks in advance.

Answer 1

But since the text length of each button may vary, each column of buttons has slightly different width. How do I make them have the same width?

• simple solution is to use GridLayout

• GridBagLayout to create a columns, Dimension for each of column is calculated from PrefferedSize came from every JButtons in 1st row, these coordinates are used for rest of rows in the current container

EDIT

• but gbc.weightx and gbc.weighty can be used for percentages divide

• simulating GridLayout (important question is why bothering with that)

import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;

public class GridFromGridBagLayout {

    private JFrame frame = new JFrame();
    private JPanel panel = new JPanel();

    public GridFromGridBagLayout() {
        panel.setLayout(new GridBagLayout());
        GridBagConstraints gbc = new GridBagConstraints();
        for (int row = 0; row < 6; row++) {
            for (int col = 0; col < 3; col++) {
                JButton b = new JButton("(" + row + ", " + col + ")");
                b.putClientProperty("column", col);
                b.putClientProperty("row", row);
                b.addActionListener(new ActionListener() {
                    @Override
                    public void actionPerformed(ActionEvent e) {
                        JButton btn = (JButton) e.getSource();
                        System.out.println("clicked column "
                                + btn.getClientProperty("column")
                                + ", row " + btn.getClientProperty("row"));
                    }
                });
                gbc.gridx = col;
                gbc.gridy = row;
                gbc.gridwidth = gbc.gridheight = 1;
                gbc.fill = GridBagConstraints.BOTH;
                gbc.anchor = GridBagConstraints.NORTHWEST;
                gbc.weightx = 33;
                gbc.weighty = 20;
                panel.add(b, gbc);
            }
        }
        frame.add(panel);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                GridFromGridBagLayout borderPanels = new GridFromGridBagLayout();
            }
        });
    }
}

Answer 2

With the help of using GridBagConstraints you can set the width equal or as you want. follow this link for help:

GridBagConstraints

Answer 3

try this:

buttonConstraints.fill = GridBagConstraints.HORIZONTAL;