How to collect JScrollPanes into a Container variable? (urgent...)

Question

Please help me in following problem:
I can collect succesfully one JScrollPane into a Container variable allComponents and then show this Container in application window. However, I would like to collect several JScrollPanes into this same Container variable but it does not work. Should I use some kind of add command?
I tried something like
allComponents.add(jspane);
but I got error code "variable allComponents might not have been initialized" allthough I have tried my best to initialize it.
Thanks for your kind help!
Snippets from my program:
class SwingApplication implements ActionListener
public Container createComponents()
Container allComponents;
jspane = new JScrollPane(panel);
jspane2 = new JScrollPane(cards);
allComponents = jspane; // THIS WORKS BUT I WOULD LIKE TO COLLECT BOTH jspane AND jspane2 WITH ADD COMMAND
return allComponents;
class DragImage
{ public static void main(String[] args)
JFrame frame = new JFrame("SwingApplication");
SwingApplication app = new SwingApplication();
Container contents = app.createComponents();
frame.getContentPane().add(contents, BorderLayout.CENTER);
Message was edited by:
wonderful123

Answer 1

THanks for your interest!!
Perhaps I give the whole source code
The problem lies in the following place:
allComponents = jspane;
return allComponents;
I would like to use some kind of command
allComponents.add(jspane);
but it does not seem to work. I get the error "variable allComponents might not be initialized".
The program should print images in two rows. With my current knowledge i can only print one row of images.
Thanks!
import java.awt.*;
    import java.awt.event.*;
    import java.awt.datatransfer.*;
    import javax.swing.*;
class SwingApplication implements ActionListener
                                        // extends JScrollPane
   private JScrollPane jspane;
   private JScrollPane jspane_n;
   private JPanel panel;
   private JLabel label;
   private Icon icon;
   private JPanel panel2;
   private JLabel label2;
   private Icon icon2;
   private JPanel panel_n;
   private JLabel label_n;
   private Icon icon_n;
   private JTextField testText;
   private int k;
    private static String labelPrefix = "Testing: ";
    private int numClicks = 0;
    final JLabel label_testing = new JLabel(labelPrefix + "nothing");
JPanel cards; //a panel that uses CardLayout
    final String BUTTONPANEL = "JPanel with JButtons";
    final String TEXTPANEL = "JPanel with JTextField";
   public Container createComponents()
Container allComponents;
     icon = new ImageIcon("kirjain_a.gif");
     label = new JLabel();
     label.setIcon(icon);
     icon2 = new ImageIcon("kirjain_b.gif");
     label2 = new JLabel();
     label2.setIcon(icon2);
     icon_n = new ImageIcon("numero_1.gif");
     label_n = new JLabel();
     label_n.setIcon(icon_n);
label.setTransferHandler(new ImageSelection());              
label2.setTransferHandler(new ImageSelection());
label_n.setTransferHandler(new ImageSelection());
        MouseListener mouseListener = new MouseAdapter() {
          public void mousePressed(MouseEvent e) {
JComponent sourceEvent = (JComponent)e.getSource();
// Object sourceEvent = whatHappened.getSource();
if (sourceEvent == label)
    { numClicks++;
        label_testing.setText(labelPrefix + numClicks);
if (sourceEvent == label2)
numClicks--;
        label_testing.setText(labelPrefix + numClicks);
            JComponent comp = (JComponent)e.getSource();
            TransferHandler handler = comp.getTransferHandler();
            handler.exportAsDrag(comp, e, TransferHandler.COPY);
       label.addMouseListener(mouseListener);
       label2.addMouseListener(mouseListener);  
       label_n.addMouseListener(mouseListener);  
     panel = new JPanel();
// panel.setLayout(new GridLayout(1,3));
     panel.add(label);
     panel.add(label2);
     panel_n = new JPanel();
     panel_n.add(label_n);
//Create the panel that contains the "cards".
        cards = new JPanel(new CardLayout());
        cards.add(panel_n, BUTTONPANEL);
        cards.add(panel_n, TEXTPANEL);
     panel.add(label_testing);
      jspane = new JScrollPane(panel);
      jspane_n = new JScrollPane(cards);
  //   jspane.setLayout(new GridLayout(3,2));      
  //   jspane.getViewport().add(panel);
  //   jspane_n.getViewport().add(cards);
  //    allComponents.add(panel, BorderLayout.PAGE_START);
  //    allComponents.add(cards, BorderLayout.CENTER);
  //     allComponents.add(jspane);
  //     allComponents.add(jspane_n);
     allComponents = jspane;
     return allComponents;
                                       //     label.addActionListener(this);
                                       //     k=0;
public void actionPerformed(ActionEvent whatHappened)
  { Object sourceEvent = whatHappened.getSource();
    if (sourceEvent == label)
    { numClicks++;
        label_testing.setText(labelPrefix + numClicks);
//    repaint();
} // end class OwnPanel
class CloserClass extends WindowAdapter
{ public void windowClosing(WindowEvent e)
   { System.exit(0);
class DragImage
{ public static void main(String[] args)
       JFrame frame = new JFrame("SwingApplication");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        SwingApplication app = new SwingApplication();
        Container contents = app.createComponents();
        frame.getContentPane().add(contents, BorderLayout.CENTER);
        //Display the window.
//    addWindowListener(new CloserClass());
        frame.pack();
        frame.setVisible(true);
    } // end class DragImage