Can't add column to table dynamically

[JOHNINALBANY]

I have added a table (JTable) to a frame. That table has been created by using Netbeans. Once my table has been created (after initcomponents()) I try to add a column to my table by using the jTable1.addColumn(new TableColumn(jTable1.getColumnCount())) statement. This stament triggers an error:

Exception in thread "AWT-EventQueue-0" java.lang.ArrayIndexOutOfBoundsException: 4 >= 4

What am I missing here?

Thanks



************************************************** ********************************************



import javax.swing.table.*;
import javax.swing.table.TableColumn;

public class MyTable extends javax.swing.JFrame {

/** Creates new form MyTable */
public MyTable() {
TableColumn tc = new TableColumn();
tc.setModelIndex(4);

initComponents();

//*************************************
//**************************************
// The below statement triggers an error. What happens?
jTable1.addColumn(new TableColumn(jTable1.getColumnCount()));
}

/** This method is called from within the constructor to
* initialize the form.
* WARNING: Do NOT modify this code. The content of this method is
* always regenerated by the Form Editor.
*/
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {

jScrollPane1 = new javax.swing.JScrollPane();
jTable1 = new javax.swing.JTable();

setDefaultCloseOperation(javax.swing.WindowConstan ts.EXIT_ON_CLOSE);

jTable1.setModel(new javax.swing.table.DefaultTableModel(
new Object [][] {
{null, null, null, null},
{null, null, null, null},
{null, null, null, null},
{null, null, null, null}
},
new String [] {
"Title 1", "Title 2", "Title 3", "Title 4"
}
));
jScrollPane1.setViewportView(jTable1);

javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout .Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILI NG, layout.createSequentialGroup()
.addContainerGap(15, Short.MAX_VALUE)
.addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 375, javax.swing.GroupLayout.PREFERRED_SIZE)
.addContainerGap())
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout .Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILI NG, layout.createSequentialGroup()
.addContainerGap(14, Short.MAX_VALUE)
.addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 275, javax.swing.GroupLayout.PREFERRED_SIZE)
.addContainerGap())
);

pack();
}// </editor-fold>

/**
* @param args the command line arguments
*/
public static void main(String args[]) {
java.awt.EventQueue.invokeLater(new Runnable() {

public void run() {
new MyTable().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JScrollPane jScrollPane1;
private javax.swing.JTable jTable1;
// End of variables declaration
}

[DarrylBurke]

Moved from New to Java.

Please go through the following links:
Forum Rules
Guide For New Members
BB Code List - Java Programming Forum

db

[DarrylBurke]

Also, a visual designer is not a beginners' tool. Hand code your GUIs until you're sufficiently familiar with the API to know where to look to add features in a visually designed Swing GUI. By which time you'll already have discovered that it's not worth the time and effort, unless you plan to make a living as a GUI designer/coder.

db

[DarrylBurke]

I see that you didn't bother to return to 4 threads you started. In the two that you did return to, only one response has a word of thanks to the member who helped you.

Not the best way to continue to get free help on a forum, that.

db