trying to center buttons with fixed sizes

[Karen Nelson]

Hi,

Is there any easy way to vertically center buttons in a panel? I am trying to display a column of buttons at a size of 60x60 pixels for each button. The code below does everything except the centering fine -- but of course if I add the buttons to the CENTER of the panel, they get stretched.

I guess I could use an empty border around the panel, and calculate its size by subtracting the size of the buttons from the height of the window etc, but is there an easier way?

Thank you!

  
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
 
public class BadGui{
 
public static void main (String[] args) {
BadGui gui = new BadGui();
gui.go();
} //main
 
public void go() {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

GridLayout buttonLO = new GridLayout(0,1); 
buttonLO.setHgap(10); 
buttonLO.setVgap(10);
JPanel buttonPanel = new JPanel(buttonLO);
buttonPanel.add(new MyButton("1"));
buttonPanel.add(new MyButton("2"));
buttonPanel.add(new MyButton("3"));
buttonPanel.add(new MyButton("4"));
buttonPanel.add(new MyButton("5"));
JPanel subPanel = new JPanel(new BorderLayout());
subPanel.add(buttonPanel, BorderLayout.SOUTH);
 
JPanel graphPanel = new JPanel();
graphPanel.setBackground(new Color(255,235,255));
graphPanel.add(new JButton("graph goes here"));
 

frame.getContentPane().add(graphPanel, BorderLayout.CENTER);
frame.getContentPane().add(subPanel, BorderLayout.WEST);
 
frame.setSize(900,650);
frame.setVisible(true);

} //go
 
private class MyButton extends JButton {
public MyButton(String s) {super(s);}
public Dimension getPreferredSize() 
{return(new Dimension(60,60));}
public Dimension getMinimumSize() 
{return(new Dimension(60,60));}
public Dimension getMaximumSize() 
{return(new Dimension(60,60));}
} //inner class MyButton
 

 
} //BadGui
 

[Michael Dunn]

change this
JPanel subPanel = new JPanel(new BorderLayout());
subPanel.add(buttonPanel, BorderLayout.SOUTH);

to this
JPanel subPanel = new JPanel(new GridBagLayout());
subPanel.add(buttonPanel, new GridBagConstraints());

unless you intend adding something else to 'subPanel'
(it being a borderlayout, and specifying south)

[Karen Nelson]

Wow, thank you! From what I read, GridBagLayout seemed to complicated to use at all by hand. Works like a charm.
-Karen