How to Select and Display an Image File in Java Swing

Question

How can I create a Java Swing application to browse for an image file and then display that image?

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import javax.imageio.ImageIO;

public class ImageDisplayApp {
    public static void main(String[] args) {
        JFrame frame = new JFrame("Image Display");
        JButton button = new JButton("Browse");
        JLabel label = new JLabel();

        button.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                JFileChooser fileChooser = new JFileChooser();
                int returnValue = fileChooser.showOpenDialog(null);
                if (returnValue == JFileChooser.APPROVE_OPTION) {
                    File selectedFile = fileChooser.getSelectedFile();
                    try {
                        Image img = ImageIO.read(selectedFile);
                        label.setIcon(new ImageIcon(img));
                    } catch (IOException ex) {
                        ex.printStackTrace();
                    }
                }
            }
        });

        frame.setLayout(new BorderLayout());
        frame.add(button, BorderLayout.NORTH);
        frame.add(label, BorderLayout.CENTER);
        frame.setSize(500, 500);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
    }
}

Answer

In this guide, we'll create a simple Java Swing application that allows users to browse for an image file and display it within the application window. We will use `JFileChooser` for file selection and `JLabel` for image display.

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import javax.imageio.ImageIO;

Causes

The need to visually represent data or provide graphical content in Java applications.
User-friendly interfaces require image upload and display capabilities.

Solutions

Implement a JFileChooser to allow users to select image files from their file system.
Use ImageIO to read and display the selected image using a JLabel.

Common Mistakes

Mistake: Forgetting to handle exceptions when loading the image.

Solution: Always include try-catch blocks to handle IOExceptions when reading files.

Mistake: Not setting the size of the JFrame properly, causing images to appear too small or cut off.

Solution: Set the frame size according to the expected image dimensions or use pack() to resize based on content.

Helpers

Java Swing
browse for image Java
display image Java Swing
JFileChooser example
Java image upload