JTextField input check (errorDialog if invalid) & JComboBox Focus

Question

I have a JTextfield which does an input check when the JTextField focus listener's focusLost method is called.
If I loose focus by clicking in on a JComboBox. The check gets done ok and focus is returned appropriately to the JTextField without any problems.
But if I try to show an errorDialog when the input is incorrect, the focus is returned to the JTextField without any problems, but the JComboBox remains highlighted as though it is still selected!
I am using sdk 1.4... on a linux box. does anyone know why this happens? and can anyone provide a clean solution to this?
Thanx,
Diego Paloschi.

Answer 1

Hello Kleopatra,
Here's a little demo:
import javax.swing.*;
import javax.swing.event.*;
public class Debug extends JPanel
private JTextField t1;
private JComboBox c1;
private T1Verifier t1Verifier;
public void init()
     t1 = new JTextField("20", 10);
     t1.setInputVerifier(new T1Verifier(this));
     String[] s = {"v1","v2","v3"};
     c1 = new JComboBox(s);
     add(t1);
     add(c1);
public static void main(String s[])
     Debug d = new Debug();
     d.init();
     JFrame f = new JFrame("Debug");
     f.getContentPane().add(d);
     f.setSize(300,300);
     f.setVisible(true);
class T1Verifier extends InputVerifier
private Debug debug;
public T1Verifier(Debug debug)
     this.debug = debug;
public boolean verify(JComponent input)
     JTextField tf = (JTextField) input;
     float value = Float.parseFloat(tf.getText());
     boolean inRange = (value >= 0) && ( value <= 10);
     return inRange;
public boolean shouldYieldFocus(JComponent input)
     boolean valid = super.shouldYieldFocus(input);
     JTextField tf = (JTextField) input;
     if ( !valid ) {
     tf.requestFocus();
     JOptionPane d = new JOptionPane();
     d.showMessageDialog(debug, "Out Of Range.", "ERROR" , JOptionPane.ERROR_MESSAGE);
     return valid;
Even if u comment out the JOptionPane and just make the inputverifier return control to the textfield it still doesn't work! What am I missing? Or how would u doi it?