Hvorfor virker samme kode ikke

Jeg har prøvet at kalde en metode to steder, men den virker kun som del af constructoren : public topFrame()
ikke som event fra knap: jButton1ActionPerformed(java.awt.event.ActionEvent evt)

Hvorfor?

Her er koden

/*
* topFrame.java
*
* Created on 4. december 2002, 18:54
*/


/**
*
* @author  KP
* @version
*/
import javax.swing.*;

public class topFrame extends javax.swing.JFrame {

    /** Creates new form topFrame */
    public topFrame() {
        initComponents ();
        pack ();   
        this.setSize(300,300);
        // Her er første kald - det virker
        // knappen kan ses
        doit(25, "1");
    }
   
    private void doit(int y, String titel)
    {
        Box b = Box.createHorizontalBox();
        JButton btn;
        b.add(btn = new JButton("titel"));
        getContentPane().add(b);               
        b.setBounds(25,y,100,20);       
    }

    /** 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 FormEditor.
    */
    private void initComponents() {
        jButton1 = new javax.swing.JButton();
        getContentPane().setLayout(null);
        addWindowListener(new java.awt.event.WindowAdapter() {
            public void windowClosing(java.awt.event.WindowEvent evt) {
                exitForm(evt);
            }
        }
        );
       
        jButton1.setText("jButton2");
        jButton1.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton1ActionPerformed(evt);
            }
        }
        );
       
        getContentPane().add(jButton1);
        jButton1.setLocation(200, 70);
        jButton1.setSize(jButton1.getPreferredSize());
       
    }

  private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
// Add your handling code here:
    // det virker ikke - knappen kommer ikke frem!
    doit(55, "2");       
  }

    /** Exit the Application */
    private void exitForm(java.awt.event.WindowEvent evt) {
        System.exit (0);
    }

    /**
    * @param args the command line arguments
    */
    public static void main (String args[]) {
        new topFrame ().show ();
    }


    // Variables declaration - do not modify
    private javax.swing.JButton jButton1;
    // End of variables declaration
   
}