/* * Copyright (c) 2000 David Flanagan.  All rights reserved. * This code is from the book Java Examples in a Nutshell, 2nd Edition. * It is provided AS-IS, WITHOUT ANY WARRANTY either expressed or implied. * You may study, use, and modify it for any non-commercial purpose. * You may distribute it non-commercially as long as you retain this notice. * For a commercial use license, or to purchase the book (recommended), * visit http://www.davidflanagan.com/javaexamples2. */package com.davidflanagan.examples.gui;import java.awt.*;import javax.swing.*;import javax.swing.border.*;public class BoxLayoutPane extends JPanel {    public BoxLayoutPane() {	// Use a BorderLayout layout manager to arrange various Box components	this.setLayout(new BorderLayout());	// Give the entire panel a margin by adding an empty border	// We could also do this by overriding getInsets()	this.setBorder(new EmptyBorder(10,10,10,10));	// Add a plain row of buttons along the top of the pane	Box row = Box.createHorizontalBox();	for(int i = 0; i < 4; i++) {	    JButton b = new JButton("B" + i);	    b.setFont(new Font("serif", Font.BOLD, 12+i*2));	    row.add(b);	}	this.add(row, BorderLayout.NORTH);	// Add a plain column of buttons along the right edge	// Use BoxLayout with a different kind of Swing container	// Give the column a border: can't do this with the Box class	JPanel col = new JPanel();	col.setLayout(new BoxLayout(col, BoxLayout.Y_AXIS));	col.setBorder(new TitledBorder(new EtchedBorder(), "Column"));	for(int i = 0; i < 4; i++) {	    JButton b = new JButton("Button " + i);	    b.setFont(new Font("sanserif", Font.BOLD, 10+i*2));	    col.add(b);	}	this.add(col, BorderLayout.EAST); // Add column to right of panel	// Add a button box along the bottom of the panel.  	// Use "Glue" to space the buttons evenly 	Box buttonbox = Box.createHorizontalBox();	buttonbox.add(Box.createHorizontalGlue());     // stretchy space	buttonbox.add(new JButton("Okay"));	buttonbox.add(Box.createHorizontalGlue());     // stretchy space	buttonbox.add(new JButton("Cancel"));	buttonbox.add(Box.createHorizontalGlue());     // stretchy space	buttonbox.add(new JButton("Help"));	buttonbox.add(Box.createHorizontalGlue());     // stretchy space	this.add(buttonbox, BorderLayout.SOUTH);	// Create a component to display in the center of the panel	JTextArea textarea = new JTextArea();	textarea.setText("This component has 12-pixel margins on left and top"+			 " and has 72-pixel margins on right and bottom.");	textarea.setLineWrap(true);	textarea.setWrapStyleWord(true);	// Use Box objects to give the JTextArea an unusual spacing	// First, create a column with 3 kids.  The first and last kids	// are rigid spaces.  The middle kid is the text area	Box fixedcol = Box.createVerticalBox();	fixedcol.add(Box.createVerticalStrut(12));  // 12 rigid pixels	fixedcol.add(textarea);          // Component fills in the rest	fixedcol.add(Box.createVerticalStrut(72));  // 72 rigid pixels	// Now create a row.  Give it rigid spaces on the left and right,	// and put the column from above in the middle.	Box fixedrow = Box.createHorizontalBox();	fixedrow.add(Box.createHorizontalStrut(12));	fixedrow.add(fixedcol);	fixedrow.add(Box.createHorizontalStrut(72));	// Now add the JTextArea in the column in the row to the panel	this.add(fixedrow, BorderLayout.CENTER);    }}