Can't add in Swing components with Background

Question

Alright, so I'm trying to add a background to an application I made. Looking through a bunch of 'tutorials', I found what I was looking for. And after trying to add the components I had on the application back again over and over, failing each time, I decided to finally come here.
Could anybody please tell me how I'd go about, where in the code, I would go about adding the components such as JLabels and JProgressBars again?
Thanks in advance,
Zach
import java.awt.event.*;
import javax.swing.*;
import java.awt.*;
public class Main extends JFrame
     JScrollPane scrollPane;
     ImageIcon icon;
     JFrame mainFrame;
     JTextArea textArea;
     JProgressBar progressBar;
     public Main()
          mainFrame = new JFrame("WQI - Sending data");
          mainFrame.setUndecorated(true);
          progressBar = new JProgressBar(0,100);
          progressBar.setPreferredSize(new Dimension(384,27));
          progressBar.setStringPainted(true);
          progressBar.setValue(65);
         icon = new ImageIcon("ScapeGaming.jpg");
         textArea = new JTextArea() {
           Image image = icon.getImage();
           {setOpaque(false);}
           public void paintComponent (Graphics g) {
             g.drawImage(image, 0, 0, this);
             super.paintComponent(g);
          textArea.disable();
         scrollPane = new JScrollPane(textArea);
         Container content = mainFrame.getContentPane();
         content.add(scrollPane, BorderLayout.CENTER);
         mainFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
         mainFrame.setSize(404, 109);
          mainFrame.setLocationRelativeTo(null);
         mainFrame.setVisible(true);
     private void addComponent(Container container,Component c,int x,int y,int width,int height)
          c.setBounds(x,y,width,height);
          container.add(c);
     public static void main(String [] args)
          Main frame = new Main();
}

Answer 1

Yes, I did compile my code. It compiles fine.
And could you please explain how using BufferedImage and ImageIO would change anything?
Just to show a bit of what this topic is about, I guess:
Note the progress bar. Without the progress bar-adding lines, the background is there. With it, the progress bar is added but the background disappears (goes back to the regular 'tannish' BG.
import java.awt.event.*;
import javax.swing.*;
import java.awt.*;
public class Main extends JFrame
     JScrollPane scrollPane;
     ImageIcon icon;
     JFrame mainFrame;
     JTextArea textArea;
     JProgressBar progressBar;
     public Main()
          mainFrame = new JFrame("WQI - Sending data");
          mainFrame.setUndecorated(true);
          progressBar = new JProgressBar(0,100);
          progressBar.setPreferredSize(new Dimension(384,27));
          progressBar.setStringPainted(true);
          progressBar.setValue(65);
         icon = new ImageIcon("ScapeGaming.jpg");
         textArea = new JTextArea() {
           Image image = icon.getImage();
           {setOpaque(false);}
           public void paintComponent (Graphics g) {
             g.drawImage(image, 0, 0, this);
             super.paintComponent(g);
          textArea.disable();
         scrollPane = new JScrollPane(textArea);
         Container content = mainFrame.getContentPane();
         content.add(scrollPane, BorderLayout.CENTER);
          content.setLayout(null);
          addComponent(content, progressBar, 5, 5, 384, 27);
         mainFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
         mainFrame.setSize(404, 109);
          mainFrame.setLocationRelativeTo(null);
         mainFrame.setVisible(true);
     private void addComponent(Container container,Component c,int x,int y,int width,int height)
          c.setBounds(x,y,width,height);
          container.add(c);
     public static void main(String [] args)
          Main frame = new Main();
}