title: jbutton refuses to change transparency
body: <p>I currently have a function which sets the background and have 1 button. The button is a PNG file and is transparent, I have done all the setOpaque stuff but the button still have a white background behind it. If anyone could help will be greatly appreciated! :) </p>
  
  <p>I have attached my function below: </p>
  
  <pre><code>public JPanel createContentPane() throws IOException{
  
      //Full back pane
      JPanel fullGUI = new JPanel();
      fullGUI.setLayout(null);
  
      //background pane
      JPanel backgroundPane = new JPanel() {
          BufferedImage image = ImageIO.read(new File("UI/back2.jpg"));
  
          public void paintComponent(Graphics g) {
              super.paintComponent(g);
              g.drawImage(image, 0, 0, 1200, 750, this);
          }
      };
  
      backgroundPane.setLayout(null);
      backgroundPane.setLocation(0,0);
      backgroundPane.setSize(1200,750);
      fullGUI.add(backgroundPane);
  
      //button pane
      JPanel buttonPanel = new JPanel();
      buttonPanel.setLayout(null);
      buttonPanel.setLocation(0, 250);
      buttonPanel.setSize(1200, 500);
      fullGUI.add(buttonPanel);
  
  
      JButton playButton = new JButton(new ImageIcon(("UI/play.png")));
      playButton.setLocation(399,47);
      playButton.setSize(405,308);
      playButton.setOpaque(false);
      playButton.setContentAreaFilled(false);
      playButton.setBorderPainted(false);
      playButton.setFocusPainted(false);
      buttonPanel.add(playButton);
  
  
      fullGUI.setOpaque(true);
      return fullGUI;
  
  
  }
  </code></pre>