ImageViewer.java Source code

Introduction

Here is the source code for ImageViewer.java

Source

/*
 This program is a part of the companion code for Core Java 8th ed.
 (http://horstmann.com/corejava)
    
 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation, either version 3 of the License, or
 (at your option) any later version.
    
 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.
    
 You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;

import javax.swing.ImageIcon;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;

/**
 * A program for viewing images.
 * 
 * @version 1.22 2007-05-21
 * @author Cay Horstmann
 */
public class ImageViewer {
    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                JFrame frame = new ImageViewerFrame();
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setVisible(true);
            }
        });
    }
}

/**
 * A frame with a label to show an image.
 */
class ImageViewerFrame extends JFrame {
    public ImageViewerFrame() {
        setTitle("ImageViewer");
        setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);

        // use a label to display the images
        label = new JLabel();
        add(label);

        // set up the file chooser
        chooser = new JFileChooser();
        chooser.setCurrentDirectory(new File("."));

        // set up the menu bar
        JMenuBar menuBar = new JMenuBar();
        setJMenuBar(menuBar);

        JMenu menu = new JMenu("File");
        menuBar.add(menu);

        JMenuItem openItem = new JMenuItem("Open");
        menu.add(openItem);
        openItem.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent event) {
                // show file chooser dialog
                int result = chooser.showOpenDialog(null);

                // if file selected, set it as icon of the label
                if (result == JFileChooser.APPROVE_OPTION) {
                    String name = chooser.getSelectedFile().getPath();
                    label.setIcon(new ImageIcon(name));
                }
            }
        });

        JMenuItem exitItem = new JMenuItem("Exit");
        menu.add(exitItem);
        exitItem.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent event) {
                System.exit(0);
            }
        });
    }

    private JLabel label;

    private JFileChooser chooser;

    private static final int DEFAULT_WIDTH = 300;

    private static final int DEFAULT_HEIGHT = 400;
}