Re: Loading Jpanels according to selection

From:
Knute Johnson <nospam@rabbitbrush.frazmtn.com>
Newsgroups:
comp.lang.java.help
Date:
Wed, 28 Jul 2010 22:56:46 -0700
Message-ID:
<BK84o.48055$0A5.32428@newsfe22.iad>
On 7/28/2010 1:48 PM, tamasu wrote:

I have JcomboBox on a main Jpanel. I need to display different
controls according the selection the user makes from the JComboBox.

To facilitate the design process and to use the netbeans GUI to align
controls on the main Jpanel I would like to create the Jpanels
separately as different classes.

Can you assist on how I could load the respective Jpanels according to
the user selection or can you highlight how such a process is normally
handled, that is, how one can change the controls that are to be
displayed according to the user selection but all should be displayed
in the same location and position as the other Jpanels. For example if
a user select option A from JComboBox Panel A with a number of
controls is display, likewise if Option D is selected Panel D with a
number of controls is displayed at the same location and position as
the other JPanels including the Panel A as per this example.

Please do not hesitate to contact me if you need further
clarifications.

Thanks and regards


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

public class test extends JFrame {
     private String[] items = { "One","Two" };

     public test() {
         setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

         final JPanel p1 = new JPanel(new GridBagLayout());
         JLabel l1 = new JLabel("One");
         p1.add(l1);
         add(p1,BorderLayout.CENTER);

         final JPanel p2 = new JPanel(new GridBagLayout());
         JLabel l2 = new JLabel("Two");
         p2.add(l2);

         final JComboBox box = new JComboBox(items);
         box.addActionListener(new ActionListener() {
             public void actionPerformed(ActionEvent ae) {
                 String ac = (String)box.getSelectedItem();
                 System.out.println(ac);
                 if (ac.equals("One")) {
                     if (p1.isShowing())
                         return;
                     if (p2.isShowing())
                         remove(p2);
                     add(p1,BorderLayout.CENTER);
                     validate();
                     repaint();
                 } else if (ac.equals("Two")) {
                     if (p2.isShowing())
                         return;
                     if (p1.isShowing())
                         remove(p1);
                     add(p2,BorderLayout.CENTER);
                     validate();
                     repaint();
                 }
             }
         });
         add(box,BorderLayout.SOUTH);

         setSize(400,300);
         setVisible(true);
     }

     public static void main(String[] args) {
         EventQueue.invokeLater(new Runnable() {
             public void run() {
                 new test();
             }
         });
     }
}

--

Knute Johnson
email s/nospam/knute2010/

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