Bildminiaturansichten zu einem Layout in einem Raster hinzufügen

Problem:

Sie müssen Fügen Sie eine Sammlung von Bildern als kleine Miniaturansichten zu einem Rahmen in einem SpringLayout hinzu und zeigen Sie sie rasterf?rmig in einem Bildlaufbereich an. Die Liste der Fotos k?nnte umfangreich sein und ein Scroll-Fenster erfordern.

L?sung:

Um dies mit Swing zu erreichen, befolgen Sie diese Schritte:

1. Erstellen Sie ein JPanel für die Fotos und ein JScrollPane für das JPanel.
2. Verwenden Sie einen Layout-Manager wie FlowLayout, um die Miniaturansichten umlaufend anzuordnen, um das Anzeigen und Scrollen zu erleichtern.
3. Fügen Sie jede Miniaturansicht als JPanel hinzu, wobei das Bild entsprechend skaliert ist.
4. Fügen Sie das JScrollPane zum Rahmen hinzu und passen Sie es an Gr??e und Position mithilfe der SpringLayout-Einschr?nkungen.

Unten finden Sie ein Codebeispiel, das dies veranschaulicht L?sung:

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.FlowLayout;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileFilter;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class ImageGrid {

    public static void main(String[] args) {
        new ImageGrid();
    }

    public ImageGrid() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                }

                JFrame frame = new JFrame("Image Grid");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setLayout(new BorderLayout());

                // Create a JPanel for the photos and add it to a JScrollPane
                JPanel photoPanel = new JPanel(new WrapLayout());
                JScrollPane photoScroll = new JScrollPane(photoPanel);

                // Add the JScrollPane to the frame
                frame.add(photoScroll, BorderLayout.CENTER);

                // Create a button to scan and add the thumbnails
                JButton scanButton = new JButton("Scan");
                scanButton.addActionListener(new ActionListener() {
                    @Override
                    public void actionPerformed(ActionEvent e) {
                        // Scan for image files
                        String path = "Enter path to your image directory";
                        File[] files = new File(path).listFiles(new FileFilter() {
                            @Override
                            public boolean accept(File pathname) {
                                String name = pathname.getName().toLowerCase();
                                return pathname.isFile() && (name.endsWith(".png")
                                        || name.endsWith(".jpg")
                                        || name.endsWith(".gif"));
                            }
                        });

                        photoPanel.removeAll();
                        for (File file : files) {
                            try {
                                // Load and scale the image
                                ImagePane pane = new ImagePane(file);
                                photoPanel.add(pane);
                            } catch (Exception exp) {
                                exp.printStackTrace();
                            }
                        }
                        photoPanel.revalidate();
                        photoPanel.repaint();
                    }
                });

                // Add the scan button to the frame
                frame.add(scanButton, BorderLayout.SOUTH);

                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setResizable(true);
                frame.setVisible(true);
            }
        });
    }

    public class ImagePane extends JPanel {

        private Image img;

        public ImagePane(File source) throws IOException {
            img = ImageIO.read(source);
            if (img.getWidth(this) > 200 || img.getHeight(this) > 200) {
                int width = img.getWidth(this);
                int height = img.getWidth(this);
                float scaleWidth = 200f / width;
                float scaleHeight = 200f / height;
                if (scaleWidth > scaleHeight) {
                    width = -1;
                    height = (int)(height * scaleHeight);
                } else {
                    width = (int)(width * scaleWidth);
                    height = -1;
                }
                img = img.getScaledInstance(width, height, Image.SCALE_SMOOTH);
            }
        }

        @Override
        public Dimension getPreferredSize() {
            return new Dimension(200, 200);
        }

        @Override
        protected void paintComponent(Graphics g) {
            super.paintComponent(g);
            Graphics2D g2d = (Graphics2D) g.create();
            if (img != null) {
                // Draw the scaled image
                int x = (getWidth() - img.getWidth(this)) / 2;
                int y = (getHeight() - img.getHeight(this)) / 2;
                g2d.drawImage(img, x, y, this);
            }
            g2d.dispose();
        }
    }

    /**
     * FlowLayout subclass that fully supports wrapping of components.
     */
    public class WrapLayout extends FlowLayout {

        private Dimension preferredLayoutSize;

        /**
         * Constructs a new
         * <code>WrapLayout</code> with a left alignment and a default 5-unit
         * horizontal and vertical gap.
         */
        public WrapLayout() {
            super();
        }

        /**
         * Constructs a new
         * <code>FlowLayout</code> with the specified alignment and a default 5-unit
         * horizontal and vertical gap. The value of the alignment argument must be
         * one of
         * <code>WrapLayout</code>,
         * <code>WrapLayout</code>, or
         * <code>WrapLayout</code>.
         *
         * @param align the alignment value
         */
        public WrapLayout(int align) {
            super(align);
        }

        /**
         * Creates a new flow layout manager with the indicated alignment and the
         * indicated horizontal and vertical gaps.
         * <p>
         * The value of the alignment argument must be one of
         * <code>WrapLayout</code>,
         * <code>WrapLayout</code>, or
         * <code>WrapLayout</code>.
         *
         * @param align the alignment value
         * @param hgap the horizontal gap between components
         * @param vgap the vertical gap between components
         */
        public WrapLayout(int align, int hgap, int vgap) {
            super(align, hgap, vgap);
        }

        /**
         * Returns the preferred dimensions for this layout given the
         * <i>visible</i> components in the specified target container.
         *
         * @param target the component which needs to be laid out
         * @return the preferred dimensions to lay out the subcomponents of the
         * specified container
         */
        @Override
        public Dimension preferredLayoutSize(Container target) {
            return layoutSize(target, true);
        }

        /**
         * Returns the minimum dimensions needed to layout the <i>visible</i>
         * components contained in the specified target container.
         *
         * @param target the component which needs to be laid out
         * @return the minimum dimensions to lay out the subcomponents of the
         * specified container
         */
        @Override
        public Dimension minimumLayoutSize(Container target) {
            Dimension minimum = layoutSize(target, false);
            minimum.width -= (getHgap() + 1);
            return minimum;
        }

        /**
         * Returns the minimum or preferred dimension needed to layout the target
         * container.
         *
         * @param target target to get layout size for
         * @param preferred should preferred size be calculated
         * @return the dimension to layout the target container
         */
        private Dimension layoutSize(Container target, boolean preferred) {
            synchronized (target.getTreeLock()) {
                //  Each row must fit with the width allocated to the container.
                //  When the container width = 0, the preferred width of the container

Das obige ist der detaillierte Inhalt vonWie kann ich mit Swing ein Raster mit Bildminiaturansichten in einem scrollbaren Bedienfeld anzeigen?. Für weitere Informationen folgen Sie bitte anderen verwandten Artikeln auf der PHP chinesischen Website!