title: Adding to existing JList
body: <p>I need some help about adding items to JList. I work on some "library" kind of project. And I need to add readers to already existing JList. But when I try to add it, JList just resets, removes all the readers and starts adding readers to a new blank JList. But I don't need it to make new list but add it to the already existing one.</p>
  
  <p>I know it's something about creating new model after adding, but i don't know where to fix it.</p>
  
  <pre><code>panelHorni = new JPanel();
      listModel = new DefaultListModel();
      listCtenaru = new JList(listModel);
  
      FileInputStream fis = new FileInputStream("myjlist.bin");
      ObjectInputStream ois = new ObjectInputStream(fis);
  
      listCtenaru = (JList)ois.readObject();
  
      listScroll = new JScrollPane();
      listScroll.add(listCtenaru);
  
  
      listCtenaru.setPreferredSize(new Dimension(350, 417));
      listCtenaru.setBackground(new Color(238,238,238));
  
      panelHorni.add(listCtenaru);
  </code></pre>
  
  <p>listener</p>
  
  <pre><code> public void actionPerformed(ActionEvent e) {
  
              String jmeno = pole1.getText();
              String prijmeni = pole2.getText();
  
              listModel.addElement(jmeno +" "+ prijmeni);
              listCtenaru.setModel(listModel);
  
              pole1.setText("");
              pole2.setText("");
              pole1.requestFocus();
  </code></pre>