ImageIcon.paintIcon does not draw image on JPanel

Question

I'm trying to draw a .png on a JPanel. I imported it using an ImageIcon constructor, and drew it in my custom panel's paintComponent.

My sscce:

package mypackage;

import java.awt.Graphics;

import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JPanel;

public class MyPanel extends JPanel {

    static JFrame frame;
    static MyPanel panel;
    static ImageIcon icon;

    public static void main(String[] args) {
        icon = new ImageIcon(MyPanel.class.getResource("MyImage.png"));
        frame = new JFrame();
        panel = new MyPanel();
        frame.setSize(500, 500);
        frame.add(panel);
        frame.setVisible(true);
        frame.repaint();
    }

    @Override
    public void paintComponent(Graphics g) {
        super.paintComponent(g);
        icon.paintIcon(panel, g, 100, 100);
    }
}

I expected the image, which is just a couple shapes on a white background, to display at (100, 100) on the panel. Instead, a blank screen:

The fact that no error occurs means the program is finding the file properly.

The image is in my Eclipse project in the same package as the class:

Why is this happening? How do I fix it?

Answer 1

As the code looks correct, I suggest that the resource is not being loaded correctly.

Place the png file in your classpath. Eg. I would have a directory:

~/ProjectRoot/resources/mypackage/

Then include resources in the classpath. In eclipse you can setup the classpath via

Project -> Properties -> Java Build Path -> Add Class Folder

BufferedImage img = 
    ImageIO.read(MyPanel.class.getResourceAsStream("MyImage.png"));

That throws an exception if the image isn't found. You can use it to make an ImageIcon.