Split image into clickable regions

Question

Is there any way to split an image to region (right now it\'s JLabel but I can change it if necessary)?
I use swing in my program and I have an image (square for this ex

Answer 1

You can use the getSubImage() method of BufferedImage, illustrated here and here. The example also uses JLabel, but you can add the Icon to a JButton that can be clicked. There are several ways for a button to remember details about it's icon:

• Subclass JButton and add a suitable field.
• Add a client property to the parent JComponent.
• Use the name property of the parent Component.

Answer 2

Have a look at what I have made:

This is the image I used for testing:

After image has been split:

And here is the source:

import java.awt.Graphics2D;
import java.awt.GridLayout;
import java.awt.Toolkit;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.SwingUtilities;

public class Test {

    private JFrame frame;
    private JLabel[] labels;
    private static String imagePath = "c:/test.jpg";
    private final int rows = 3; //You should decide the values for rows and cols variables
    private final int cols = 3;
    private final int chunks = rows * cols;
    private final int SPACING = 10;//spacing between split images

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                new Test().createAndShowUI();
            }
        });
    }

    private void createAndShowUI() {
        frame = new JFrame("Test");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        initComponents();
        frame.setResizable(false);
        frame.pack();
        frame.setVisible(true);
    }

    private void initComponents() {

        BufferedImage[] imgs = getImages();

        //set contentpane layout for grid
        frame.getContentPane().setLayout(new GridLayout(rows, cols, SPACING, SPACING));

        labels = new JLabel[imgs.length];

        //create JLabels with split images and add to frame contentPane
        for (int i = 0; i < imgs.length; i++) {
            labels[i] = new JLabel(new ImageIcon(Toolkit.getDefaultToolkit().createImage(imgs[i].getSource())));
            frame.getContentPane().add(labels[i]);
        }
    }

    private BufferedImage[] getImages() {
        File file = new File(imagePath); // I have bear.jpg in my working directory
        FileInputStream fis = null;
        try {
            fis = new FileInputStream(file);
        } catch (FileNotFoundException ex) {
            Logger.getLogger(Test.class.getName()).log(Level.SEVERE, null, ex);
        }
        BufferedImage image = null;
        try {
            image = ImageIO.read(fis); //reading the image file
        } catch (IOException ex) {
            Logger.getLogger(Test.class.getName()).log(Level.SEVERE, null, ex);
        }
        int chunkWidth = image.getWidth() / cols; // determines the chunk width and height
        int chunkHeight = image.getHeight() / rows;
        int count = 0;
        BufferedImage imgs[] = new BufferedImage[chunks]; //Image array to hold image chunks
        for (int x = 0; x < rows; x++) {
            for (int y = 0; y < cols; y++) {
                //Initialize the image array with image chunks
                imgs[count] = new BufferedImage(chunkWidth, chunkHeight, image.getType());

                // draws the image chunk
                Graphics2D gr = imgs[count++].createGraphics();
                gr.drawImage(image, 0, 0, chunkWidth, chunkHeight, chunkWidth * y, chunkHeight * x, chunkWidth * y + chunkWidth, chunkHeight * x + chunkHeight, null);
                gr.dispose();
            }
        }
        return imgs;
    }
}

The only flaw is I haven't checked if the image is larger then the screen which could cause problems, that would be resolved by a simple image resize using getScaledInstance(int x,int y, int width, in height) on the image and the separating it into chunks.

Update

Sorry I missed the part if the question in Shapes, have a look at draw(Shape s) method of Graphics2D/Graphics.

I read this:

Any Shape object can be used as a clipping path that restricts the portion of the drawing area that will be rendered. The clipping path is part of the Graphics2D context; to set the clip attribute, you call Graphics2D.setClip and pass in the Shape that defines the clipping path you want to use.

See here for clipping an u]image to a shape: Clipping the Drawing Region

References:

• How to Split an Image into Chunks - Java ImageIO