JComboBox.setPopupVisible() and focus

Question

Hello,
the following code demonstrates that always when the combobox is editable and the standard focus sequence is modified, a setPopupVisible(true) indeed opens the popup, but it is immediately closed again. Is anything wrong with the code?
Although there are quite a number of JComboBox bugs in the database, I did not find this one. If it is a bug, of course I would be interested in a workaround.
Regards
J�rg
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Y extends JFrame
  private JComboBox cmb;
  public Y()
  { setSize(300,300);
    setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    Container cp= getContentPane();
    cp.setLayout(null);
    final JCheckBox cb= new JCheckBox("Combo editable");
    cb.setBounds(80,30,130,20);
    cb.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
     cmb.setEditable(cb.isSelected());
    final JTextField tf1= new JTextField();
    tf1.setBounds(50,60,60,20);
    tf1.addFocusListener(new FocusAdapter() {
      public void focusLost(FocusEvent evt) {
     if (!tf1.getText().equals("ee")) {
       cmb.requestFocusInWindow(); // Prevents popup to stay open.
       cmb.setPopupVisible(true);
       System.out.println(cmb.isVisible());
    JTextField tf2= new JTextField();
    tf2.setBounds(150,60,60,20);
    tf2.addFocusListener(new FocusAdapter() {
      public void focusLost(FocusEvent evt) {
     cmb.setPopupVisible(true);
    cmb = new JComboBox(new String[]{"Item 1", "Item 2", "Item 3", "Item 4"});
    cmb.setBounds(100,90,50,20);
    cmb.setSelectedIndex(-1);
    System.out.println("LightWeight: "+cmb.isLightWeightPopupEnabled());
    cp.add(cb);
    cp.add(tf1);
    cp.add(tf2);
    cp.add(cmb);
    setVisible(true);
    tf1.requestFocusInWindow();
  public static void main(String args[])
  { java.awt.EventQueue.invokeLater(new Runnable()
    { public void run()
      { new Y();
}

Answer 1

Well, there's two things I note. The first is you're printing out the comboBox's visible status, which is always true, when you're probably trying to get the comboBox's popup's visible status.
The second thing is the cause of your problem. You request focus on the combo box. When it is editable, however, it is the editor component that gets the focus, not the combo box. So, the popup is made visible and then the editor component loses focus because the combo box gets focus, and so the popup is hidden.
This change does what you want, I think:
    tf1.addFocusListener(new FocusAdapter() {
      public void focusLost(FocusEvent evt) {
    if (!tf1.getText().equals("ee")) {
        if ( cmb.isEditable() )
            cmb.getEditor().getEditorComponent().requestFocusInWindow();
        else
            cmb.requestFocusInWindow(); // Prevents popup to stay open.
      cmb.setPopupVisible(true);
      System.out.println(cmb.isVisible());
    });