Re: Simple BorderLayout problem

On 2010-02-16 06:17, Knute Johnson wrote:


Thanks for that link, I will be sure to bookmark it! Below is my updated
program: It has a "group panel" in the center. The group panel holds two
buttons on the same line with space around them. At the bottom of
frame's content pane I have label acting as a status bar.

I know the code is overly verbose, it's for my learning purposes. I
can't say I have mastered GridBagLayout at all yet, but I can say I will
be using it from now on as much as I can so I do learn it.

One question about my program code, if I want to make the buttons have
the same width, how should I do that? Basically I want the button with
longest text to have its preferred width then increase the width of any
thinner buttons. In my case the button labeled "Open BioModel" should
have its width increased to match that of the button labeled "Load Saved
Session".

Here's the complete code:

package main;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;

import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.border.TitledBorder;

public class CenteredGroup {

    public CenteredGroup() {
       frame = new JFrame("BioModel explorer");

       frame.setSize(640, 480);
       frame.setLocationRelativeTo(null);
       frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

       contentPane = (JPanel)frame.getContentPane();

       contentPane.setLayout(new GridBagLayout());

       JPanel groupPanel = new JPanel();

       groupPanel.setPreferredSize(new Dimension(480, 100));
       groupPanel.setBorder(new TitledBorder("Start a new session by
opening a BioModel or load a previously saved session"));
       groupPanel.setLayout(new GridBagLayout());

       JButton b1 = new JButton("Open BioModel");
       JButton b2 = new JButton("Load Saved Session");

       addButtonsToGroupPanel(groupPanel, b1, b2);

       addGroupPanel(groupPanel);

       statusLabel = new JLabel("My Status Bar");

       statusLabel.setBorder(BorderFactory.createLineBorder(Color.BLUE,10));

       addStatusLabel(statusLabel);
    }

    public void show() {
       frame.setVisible(true);
    }

    protected void addGroupPanel(JPanel groupPanel) {
       GridBagConstraints gbc = new GridBagConstraints();

       gbc.gridx = 1;
       gbc.gridy = 1;
       gbc.gridwidth = 1;
       gbc.gridheight = 1;
       gbc.weightx = 1;
       gbc.weighty = 1;
       gbc.anchor = GridBagConstraints.CENTER;
       gbc.fill = GridBagConstraints.NONE;

       contentPane.add(groupPanel, gbc);
    }

    protected void addStatusLabel(JLabel statusLabel) {
       GridBagConstraints gbc = new GridBagConstraints();

       gbc.gridx = 0;
       gbc.gridy = 2;
       gbc.gridwidth = 3;
       gbc.gridheight = 1;
       gbc.weightx = 0;
       gbc.weighty = 0;
       gbc.anchor = GridBagConstraints.LAST_LINE_START;
       gbc.fill = GridBagConstraints.HORIZONTAL;

       frame.getContentPane().add(statusLabel, gbc);
    }

    protected void addButtonsToGroupPanel(JPanel groupPanel, JButton b1,
JButton b2) {
       GridBagConstraints gbc = new GridBagConstraints();

       gbc.gridx = 0;
       gbc.gridy = 0;
       gbc.gridwidth = 1;
       gbc.gridheight = 1;
       gbc.weightx = 0.5;
       gbc.weighty = 0;
       gbc.anchor = GridBagConstraints.CENTER;
       gbc.fill = GridBagConstraints.NONE;

       groupPanel.add(b1, gbc);

       gbc.gridx = 1;

       groupPanel.add(b2, gbc);
    }

    public static void main(String[] args) {
       CenteredGroup inst = new CenteredGroup();

       inst.show();
    }

    private JFrame frame = null;

    private JPanel contentPane = null;

    private JLabel statusLabel = null;
}

- F