Why Isn't My Extended JPanel's paintComponent() Method Being Called Despite Using repaint()?

Program not accessing method paintComponent() of extended JPanel class

Issue

The provided code features a JFrame and its corresponding JPanel extension. While the repaint() method of the JPanel is being called repeatedly, it fails to execute the paintComponent() method. This has led to the suspicion that the imageDimension object could be the source of the issue.

Solution

Although the supplied context doesn't explicitly reference byte arrays, it appears that the objective is to create grayscale thumbnails and assign them to a component's icon. The sample code below offers a method for converting existing sample icons to grayscale and using setIcon() to update the component. This approach can be applied to any image.

It's worth noting that the aforementioned grayscale conversion can be achieved using ColorConvertOp or by updating the component itself instead of its icon.

import java.awt.*;<br>import javax.swing.*;</p>
<p>public class IconExample {</p>
<div class="code" style="position:relative; padding:0px; margin:0px;"><pre class="brush:php;toolbar:false">public static void main(String[] args) {
    // Create a list of icons
    List<Icon> icons = new ArrayList<>();
    icons.add(new ImageIcon("image1.png"));
    icons.add(new ImageIcon("image2.png"));

    // Create a panel to hold the icons
    JPanel panel = new JPanel();
    panel.setLayout(new GridLayout(1, icons.size()));

    // Add the icons to the panel
    for (Icon icon : icons) {
        panel.add(new JLabel(icon));
    }

    // Create a frame for the panel
    JFrame frame = new JFrame();
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setSize(300, 300);
    frame.add(panel);

    // Make the frame visible
    frame.setVisible(true);

    // Create a timer to update the icons
    Timer timer = new Timer(1000, new ActionListener() {
        @Override
        public void actionPerformed(ActionEvent e) {
            // Shuffle the icons
            Collections.shuffle(icons);

            // Update the icons in the panel
            for (int i = 0; i < icons.size(); i++) {
                panel.getComponent(i).setIcon(icons.get(i));
            }

            // Repaint the panel
            panel.repaint();
        }
    });

    // Start the timer
    timer.start();
}