JSplitPane not displaying on screen

Question

Someone please help me. Stuck on this problem for 3 days now but just cannot see the answer. JSplitPane just does not display on screen. When I call it from within the class xer it appears as a little rectangle of about 2mm by 4 mm insize. When I call it from within actionPerformed I just do not see anything at all. I need to call it from actionPerformed as a final solution. Please give the answer based on it being called from actionPerformed. Thanks.
Peter Loo
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.table.*;
import javax.swing.tree.*;
import java.util.*;
import javax.swing.event.*;
import java.lang.*;
public class xer extends JFrame
JPanel erPanel;
Container contentPane;
public xer()
contentPane = getContentPane();
erPanel = new JPanel();
contentPane.add(erPanel);
// Menu
ErMenu erMenu = new ErMenu(contentPane, erPanel);
setJMenuBar (erMenu.getErMenuBar());
// If I call Define Report here I have small JSplitPane about 2mm by 4 mm size
new DefineReport(contentPane, erPanel);
pack();
setExtendedState(Frame.MAXIMIZED_BOTH);
setDefaultCloseOperation (DISPOSE_ON_CLOSE);
setVisible(true);
public static void main (String args[])
new xer();
* Processing for menu
class ErMenu implements ActionListener
Container contentPane;
JPanel erPanel;
JMenuBar erMenuBar;
JMenu fileMenu;
JMenu reportMenu;
JMenuItem defineMenuItem;
JMenuItem runMenuItem;
DefineReport defineReport;
StringBuffer currentScreen;
* Create menu & menubar
public ErMenu (Container contentPane, JPanel erPanel)
this.contentPane = contentPane;
this.erPanel = erPanel;
// Menu bar
erMenuBar = new JMenuBar ();
// Menu reports
reportMenu = new JMenu (" Report ");
defineMenuItem = new JMenuItem ("Define Report");
defineMenuItem.setActionCommand ("MenuItemDefineReport");
defineMenuItem.addActionListener (this);
reportMenu.add(defineMenuItem);
runMenuItem = new JMenuItem ("Run Report");
runMenuItem.setActionCommand ("MenuItemRunReport");
runMenuItem.addActionListener (this);
reportMenu.add (runMenuItem);
erMenuBar.add (reportMenu);
public JMenuBar getErMenuBar()
return erMenuBar;
public void actionPerformed (ActionEvent e)
String menuaction = e.getActionCommand();
if (menuaction.compareTo ("MenuItemDefineReport") == 0)
// If I call Define Report here I do not get the JSplitPane
defineReport = new DefineReport(this.contentPane, this.erPanel);
* Main processing for Defining a report
class DefineReport
JPanel erPanel;
Container contentPane;
JSplitPane erJSplitPane;
public DefineReport (Container contentPane, JPanel erPanel)
this.erPanel = erPanel;
this.contentPane = contentPane;
// this.contentPane.invalidate();
// this.contentPane.removeAll();
// this.erPanel.invalidate();
// this.erPanel.removeAll();
erJSplitPane = setupErJSplitPane ();
erPanel.add (erJSplitPane);
// contentPane.add(erPanel);
contentPane.setVisible(true);
} // End of constructor DefineReport
public JSplitPane setupErJSplitPane()
JScrollPane listScrollPane;
JScrollPane treeScrollPane;
listScrollPane = new JScrollPane ();
treeScrollPane = new JScrollPane ();
erJSplitPane = new JSplitPane (JSplitPane.HORIZONTAL_SPLIT,
listScrollPane, treeScrollPane);
erJSplitPane.setOneTouchExpandable (true);
erJSplitPane.setDividerLocation (50);
Dimension minSize = new Dimension (50,50);
listScrollPane.setMinimumSize (minSize);
treeScrollPane.setMinimumSize (minSize);
listScrollPane.setBackground(Color.red);
listScrollPane.setForeground(Color.red);
treeScrollPane.setBackground(Color.blue);
treeScrollPane.setForeground(Color.blue);
return erJSplitPane;
} // End of class DefineReport

Answer 1

I have read all the tutorials that I can find and it
seems (at least to me) that I have done everything
necessary. I am really quite new to Java.
Peter LooIts called a learning curve dear, we've all been there