Re: How do I get a selected value from JDialog?

From:
Knute Johnson <nospam@rabbitbrush.frazmtn.com>
Newsgroups:
comp.lang.java.programmer
Date:
Mon, 21 Aug 2006 08:35:59 -0700
Message-ID:
<IokGg.40503$k54.29789@newsfe11.phx>
mwmann wrote:

Hi everyone

I have a class which extends JDialog, its purpose is to show a list of
values retrieved from a database, which will allow the user to select
from a table in this Dialoge, the selected string value in the dialog
should be accessable from the Parent form when the dialog is closed/OK
pressed- or a text field in the parent field populated when OKAY
clicked.

How do go about retrieving the user selected value from the dialog ?

Code samples/ psuedo code would be helpfull.

Thanks


Here is a simple working example for you. There are literally hundreds
of ways to do this task but these are the critical elements.

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class test4 {
     static JTextField tf;
     static JButton b;

     public static void main(String[] args) {

         class DataDialog extends JDialog {
             public String result;

             public DataDialog(Frame parent, boolean modal, String[] data) {
                 super(parent,modal);

                 final JComboBox bx = new JComboBox(data);
                 add(bx,BorderLayout.WEST);
                 final JButton b = new JButton("OKAY");
                 b.addActionListener(new ActionListener() {
                     public void actionPerformed(ActionEvent ae) {
                         result = (String)bx.getSelectedItem();
                         setVisible(false);
                         dispose();
                     }
                 });
                 add(b,BorderLayout.EAST);
                 pack();
                 setLocationRelativeTo(parent);
             }
         }

         Runnable r = new Runnable() {
             public void run() {
                 final JFrame f = new JFrame();
                 f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

                 // text field to hold result
                 tf = new JTextField();
                 f.add(tf,BorderLayout.NORTH);

                 b = new JButton("Get Data From DB");
                 b.addActionListener(new ActionListener() {
                     public void actionPerformed(ActionEvent ae) {
                         // disable button so you can't try to retrieve
while
                         // the previous request is going on
                         b.setEnabled(false);
                         // it could take a while so retrieve the data in
                         // another thread
                         Runnable r = new Runnable() {
                             public void run() {
                                 // simulate retrieving data from db
                                 try { Thread.sleep(1000); }
                                 catch (InterruptedException ie) { }
                                 // this is simulated data
                                 String[] s = {"one","two","three","four"};
                                 // create dialog
                                 DataDialog d = new DataDialog(f,true,s);
                                 d.setVisible(true);
                                 // get data from public variable in
DataDialog
                                 // and show data in text field in frame
                                 tf.setText(d.result);
                                 // re-enable button
                                 b.setEnabled(true);
                             }
                         };
                         new Thread(r).start();
                     }
                 });
                 f.add(b,BorderLayout.SOUTH);
                 f.pack();
                 f.setLocationRelativeTo(null);
                 f.setVisible(true);
             }
         };
         EventQueue.invokeLater(r);
     }
}

--

Knute Johnson
email s/nospam/knute/

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