FocusTraversalDemo.java Source code

Java tutorial

Introduction

Here is the source code for FocusTraversalDemo.java

Source

/* From http://java.sun.com/docs/books/tutorial/index.html */

/*
 * Copyright (c) 2006 Sun Microsystems, Inc. All Rights Reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * -Redistribution of source code must retain the above copyright notice, this
 *  list of conditions and the following disclaimer.
 *
 * -Redistribution in binary form must reproduce the above copyright notice,
 *  this list of conditions and the following disclaimer in the documentation
 *  and/or other materials provided with the distribution.
 *
 * Neither the name of Sun Microsystems, Inc. or the names of contributors may
 * be used to endorse or promote products derived from this software without
 * specific prior written permission.
 *
 * This software is provided "AS IS," without a warranty of any kind. ALL
 * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
 * ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
 * OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MIDROSYSTEMS, INC. ("SUN")
 * AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE
 * AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
 * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST
 * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL,
 * INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY
 * OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE,
 * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 *
 * You acknowledge that this software is not designed, licensed or intended
 * for use in the design, construction, operation or maintenance of any
 * nuclear facility.
 */

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Container;
import java.awt.FocusTraversalPolicy;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.BorderFactory;
import javax.swing.JCheckBox;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTable;
import javax.swing.JTextField;

/*
 * FocusTraversalDemo.java is a 1.4 example that requires no other files.
 */
public class FocusTraversalDemo extends JPanel implements ActionListener {

    static JFrame frame;

    JTextField tf1, tf2, tf3, tf4, tf5, tf6;

    JTable table;

    JLabel label;

    JCheckBox togglePolicy;

    static MyOwnFocusTraversalPolicy newPolicy;

    public FocusTraversalDemo() {
        super(new BorderLayout());
        newPolicy = new MyOwnFocusTraversalPolicy();

        tf1 = new JTextField("Field 1");
        tf2 = new JTextField("A Bigger Field 2");
        tf3 = new JTextField("Field 3");
        tf4 = new JTextField("A Bigger Field 4");
        tf5 = new JTextField("Field 5");
        tf6 = new JTextField("A Bigger Field 6");
        table = new JTable(4, 3);
        togglePolicy = new JCheckBox("Custom FocusTraversalPolicy");
        togglePolicy.setActionCommand("toggle");
        togglePolicy.addActionListener(this);
        togglePolicy.setFocusable(false); //Remove it from the focus cycle.
        //Note that HTML is allowed and will break this run of text
        //across two lines.
        label = new JLabel(
                "<html>Use Tab (or Shift-Tab) to navigate from component to component.<p>Control-Tab (or Control-Shift-Tab) allows you to break out of the JTable.</html>");

        JPanel leftTextPanel = new JPanel(new GridLayout(3, 2));
        leftTextPanel.add(tf1, BorderLayout.PAGE_START);
        leftTextPanel.add(tf3, BorderLayout.CENTER);
        leftTextPanel.add(tf5, BorderLayout.PAGE_END);
        leftTextPanel.setBorder(BorderFactory.createEmptyBorder(0, 0, 5, 5));
        JPanel rightTextPanel = new JPanel(new GridLayout(3, 2));
        rightTextPanel.add(tf2, BorderLayout.PAGE_START);
        rightTextPanel.add(tf4, BorderLayout.CENTER);
        rightTextPanel.add(tf6, BorderLayout.PAGE_END);
        rightTextPanel.setBorder(BorderFactory.createEmptyBorder(0, 0, 5, 5));
        JPanel tablePanel = new JPanel(new GridLayout(0, 1));
        tablePanel.add(table, BorderLayout.CENTER);
        tablePanel.setBorder(BorderFactory.createEtchedBorder());
        JPanel bottomPanel = new JPanel(new GridLayout(2, 1));
        bottomPanel.add(togglePolicy, BorderLayout.PAGE_START);
        bottomPanel.add(label, BorderLayout.PAGE_END);

        add(leftTextPanel, BorderLayout.LINE_START);
        add(rightTextPanel, BorderLayout.CENTER);
        add(tablePanel, BorderLayout.LINE_END);
        add(bottomPanel, BorderLayout.PAGE_END);
        setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
    }

    //Turn the custom focus traversal policy on/off,
    //according to the checkbox
    public void actionPerformed(ActionEvent e) {
        if ("toggle".equals(e.getActionCommand())) {
            frame.setFocusTraversalPolicy(togglePolicy.isSelected() ? newPolicy : null);
        }
    }

    /**
     * Create the GUI and show it. For thread safety, this method should be
     * invoked from the event-dispatching thread.
     */
    private static void createAndShowGUI() {
        //Make sure we have nice window decorations.
        JFrame.setDefaultLookAndFeelDecorated(true);

        //Create and set up the window.
        frame = new JFrame("FocusTraversalDemo");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        //Create and set up the content pane.
        JComponent newContentPane = new FocusTraversalDemo();
        newContentPane.setOpaque(true); //content panes must be opaque
        frame.setContentPane(newContentPane);

        //Display the window.
        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        //Schedule a job for the event-dispatching thread:
        //creating and showing this application's GUI.
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
    }

    public class MyOwnFocusTraversalPolicy extends FocusTraversalPolicy {

        public Component getComponentAfter(Container focusCycleRoot, Component aComponent) {
            if (aComponent.equals(tf1)) {
                return tf2;
            } else if (aComponent.equals(tf2)) {
                return tf3;
            } else if (aComponent.equals(tf3)) {
                return tf4;
            } else if (aComponent.equals(tf4)) {
                return tf5;
            } else if (aComponent.equals(tf5)) {
                return tf6;
            } else if (aComponent.equals(tf6)) {
                return table;
            } else if (aComponent.equals(table)) {
                return tf1;
            }
            return tf1;
        }

        public Component getComponentBefore(Container focusCycleRoot, Component aComponent) {
            if (aComponent.equals(tf1)) {
                return table;
            } else if (aComponent.equals(tf2)) {
                return tf1;
            } else if (aComponent.equals(tf3)) {
                return tf2;
            } else if (aComponent.equals(tf4)) {
                return tf3;
            } else if (aComponent.equals(tf5)) {
                return tf4;
            } else if (aComponent.equals(tf6)) {
                return tf5;
            } else if (aComponent.equals(table)) {
                return tf6;
            }
            return tf1;
        }

        public Component getDefaultComponent(Container focusCycleRoot) {
            return tf1;
        }

        public Component getLastComponent(Container focusCycleRoot) {
            return table;
        }

        public Component getFirstComponent(Container focusCycleRoot) {
            return tf1;
        }
    }
}