Resize Array Icon

Question

I am creating a small app that is like a slide show and I need to know how I can do so that in the array of the icons the images have a maximum size and do not occupy everything, since they do not appear correctly.

public class Frame extends JFrame {

    private JLabel slidesLabel = new JLabel();
    private Icon[] icons;
    private int currentSlide = -1;

    public Frame() {
        try {
            // Personally, I'd use File#listFiles to list all the
            // images in a directory, but that might be consider
            // using our initiative...

            icons = new Icon[]{
                    new ImageIcon(ImageIO.read(new File("src/WordToImage/img/prueba.png"))),
                    new ImageIcon(ImageIO.read(new File("src/WordToImage/img/prueba-2.png"))),
                    new ImageIcon(ImageIO.read(new File("src/WordToImage/img/prueba.png")))
            };
            Dimension max = new Dimension(300,600);
            slidesLabel.setMaximumSize(max);
            slidesLabel.setVerticalAlignment(JLabel.CENTER);
            slidesLabel.setHorizontalAlignment(JLabel.CENTER);
            setLayout(new BorderLayout());

            add(slidesLabel, BorderLayout.CENTER);
            slidesLabel.addMouseListener(new ClickListener());
            nextSlide();

        } catch (IOException exp) {
            exp.printStackTrace();
        }
    }

    public void nextSlide() {
        if (currentSlide < icons.length - 1) {
            currentSlide++;
            slidesLabel.setIcon(icons[currentSlide]);
        }
    }

    public static void main(String args[]) {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                    ex.printStackTrace();
                }

                Frame frame = new Frame();
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }
        });
    }

    public class ClickListener extends MouseAdapter {

        @Override
        public void mouseClicked(MouseEvent e) {
            nextSlide();
        }
    }

}

The problem is that the images do not look in an appropriate format and occupy the entire panel, making it illegible and also, it is horrible.

Thanks so much for the help.

I would also like, if possible, to add some arrows instead of clicks.

EDIT:

This is the image in the app

This is the original image

Answer 1

Please find a sample code for loading jpg files in jframe with preview icons.

import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.RenderingHints;
import java.awt.event.ActionEvent;
import java.awt.image.BufferedImage;
import java.net.MalformedURLException;
import java.util.List;

import javax.swing.AbstractAction;
import javax.swing.BorderFactory;
import javax.swing.Box;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JScrollPane;
import javax.swing.JToolBar;
import javax.swing.SwingUtilities;
import javax.swing.SwingWorker;

public class IconicImage2 extends JFrame {

    private JLabel photographLabel = new JLabel();
    private JToolBar buttonBar = new JToolBar();

    private String imagedir = "images/icons/";

    /**
     * List of all the descriptions of the image files. These correspond one to one
     * with the image file names
     */
    private String[] imageCaptions = { "Original SUNW Logo", "The Clocktower", "Clocktower from the West",
            "The Mansion", "Sun Auditorium" };

    /**
     * List of all the image files to load.
     */
    private String[] imageFileNames = { "1.jpg", "2.jpg", "3.jpg", "4.jpg" };

    /**
     * Main entry point to the demo. Loads the Swing elements on the "Event Dispatch
     * Thread".
     *
     * @param args
     */
    public static void main(String args[]) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                IconicImage2 app = new IconicImage2();
                app.setSize(new Dimension(800, 600));
                app.setVisible(true);
            }
        });
    }

    /**
     * Default constructor for the demo.
     */
    public IconicImage2() {
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setTitle("Icon Demo: Please Select an Image");

        // A label for displaying the pictures
        photographLabel.setVerticalTextPosition(JLabel.BOTTOM);
        photographLabel.setHorizontalTextPosition(JLabel.CENTER);
        photographLabel.setHorizontalAlignment(JLabel.CENTER);
        photographLabel.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
        JScrollPane scrollPane = new JScrollPane(photographLabel);
        setPreferredSize(new Dimension(450, 110));

        // We add two glue components. Later in process() we will add thumbnail buttons
        // to the toolbar inbetween thease glue compoents. This will center the
        // buttons in the toolbar.
        buttonBar.add(Box.createGlue());
        buttonBar.add(Box.createGlue());

        add(buttonBar, BorderLayout.SOUTH);
        add(scrollPane, BorderLayout.CENTER);

        setSize(400, 300);

        // this centers the frame on the screen
        setLocationRelativeTo(null);

        // start the image loading SwingWorker in a background thread
        loadimages.execute();
    }

    /**
     * SwingWorker class that loads the images a background thread and calls publish
     * when a new one is ready to be displayed.
     *
     * We use Void as the first SwingWroker param as we do not need to return
     * anything from doInBackground().
     */
    private SwingWorker<Void, ThumbnailAction> loadimages = new SwingWorker<Void, ThumbnailAction>() {

        /**
         * Creates full size and thumbnail versions of the target image files.
         */
        @Override
        protected Void doInBackground() throws Exception {
            for (int i = 0; i < imageCaptions.length; i++) {
                ImageIcon icon;
                icon = createImageIcon(imagedir + imageFileNames[i], imageCaptions[i]);

                ThumbnailAction thumbAction = null;
                if (icon != null) {

                    ImageIcon thumbnailIcon = new ImageIcon(getScaledImage(icon.getImage(), 32, 32));

                    thumbAction = new ThumbnailAction(icon, thumbnailIcon, imageCaptions[i]);

                }
                if (thumbAction != null)
                    publish(thumbAction);
            }
            // unfortunately we must return something, and only null is valid to
            // return when the return type is void.
            return null;
        }

        /**
         * Process all loaded images.
         */
        @Override
        protected void process(List<ThumbnailAction> chunks) {
            for (ThumbnailAction thumbAction : chunks) {
                JButton thumbButton = new JButton(thumbAction);
                // add the new button BEFORE the last glue
                // this centers the buttons in the toolbar
                buttonBar.add(thumbButton, buttonBar.getComponentCount() - 1);
            }
        }
    };

    /**
     * Creates an ImageIcon if the path is valid.
     * 
     * @param String
     *            - resource path
     * @param String
     *            - description of the file
     * @throws MalformedURLException 
     */
    protected ImageIcon createImageIcon(String path, String description) throws MalformedURLException {
//      java.net.URL imgURL = new java.net.URL(path);
        if (path != null) {
            return new ImageIcon(path, description);
        } else {
            System.err.println("Couldn't find file: " + path);
            return null;
        }
    }

    /**
     * Resizes an image using a Graphics2D object backed by a BufferedImage.
     * 
     * @param srcImg
     *            - source image to scale
     * @param w
     *            - desired width
     * @param h
     *            - desired height
     * @return - the new resized image
     */
    private Image getScaledImage(Image srcImg, int w, int h) {
        BufferedImage resizedImg = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
        Graphics2D g2 = resizedImg.createGraphics();
        g2.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);
        g2.drawImage(srcImg, 0, 0, w, h, null);
        g2.dispose();
        return resizedImg;
    }

    /**
     * Action class that shows the image specified in it's constructor.
     */
    private class ThumbnailAction extends AbstractAction {

        /**
         * The icon if the full image we want to display.
         */
        private Icon displayPhoto;

        /**
         * @param Icon
         *            - The full size photo to show in the button.
         * @param Icon
         *            - The thumbnail to show in the button.
         * @param String
         *            - The descriptioon of the icon.
         */
        public ThumbnailAction(Icon photo, Icon thumb, String desc) {
            displayPhoto = photo;

            // The short description becomes the tooltip of a button.
            putValue(SHORT_DESCRIPTION, desc);

            // The LARGE_ICON_KEY is the key for setting the
            // icon when an Action is applied to a button.
            putValue(LARGE_ICON_KEY, thumb);
        }

        /**
         * Shows the full image in the main area and sets the application title.
         */
        public void actionPerformed(ActionEvent e) {
            photographLabel.setIcon(displayPhoto);
            setTitle("Icon Demo: " + getValue(SHORT_DESCRIPTION).toString());
        }
    }
}

Please go through the following link which show the thumbnail icon program with an example.

https://docs.oracle.com/javase/tutorial/uiswing/components/icon.html

1. Go to Section "A More Complex Image Icon Example"
2. Refer the program "IconDemoApp.java"
3. Or Press the jnlp launch button to see the demo.