Java GUI - JButton opens another frame from another class

Question

i'm having trouble to get the 2nd frame to display the GUI Components. i've opened the frame using the JButton from the 1st frame.

Here's the screen shot

This is the first frame - ClientModule.java enter image description here

2nd frame - ClientMenu.java enter image description here

Here's the codes i've tried

ClientModule.java

import java.net.*;
import java.util.*;
import java.io.*;
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class ClientModule extends JFrame implements Runnable{

    private JPanel panel;
    private JFrame frame;
    private JLabel titleLbl, userLbl, passLbl, hostLbl, portLbl, ipLbl;
    private JTextField userTxt, hostTxt, portTxt, ipTxt;
    private JPasswordField passTxt;
    private JButton loginBtn;

    public static void main(String[] args)
    {
        new ClientModule().run();
    }

    public ClientModule()
    {
        frame = new JFrame("DMS(Drawing Message System)");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setResizable(false);

        panel = new JPanel();
        panel.setPreferredSize(new Dimension(500,500));
        panel.setLayout(new FlowLayout());

        titleLbl = new JLabel("LogIn to Drawing Message System(DMS)");
        titleLbl.setFont(new Font("Rockwell Condensed",Font.BOLD,28));      
        userLbl = new JLabel("Username:");
        passLbl = new JLabel("Password:");
        hostLbl = new JLabel("Hostname:");
        portLbl = new JLabel("Port No.:");
        ipLbl = new JLabel("IP Address:");

        userTxt = new JTextField();
        userTxt.setPreferredSize(new Dimension(100,30));

        passTxt = new JPasswordField();
        passTxt.setEchoChar('*');
        passTxt.setPreferredSize(new Dimension(100,30));

        portTxt = new JTextField();
        portTxt.setPreferredSize(new Dimension(100,30));

        ipTxt = new JTextField();
        ipTxt.setPreferredSize(new Dimension(100,30));

        hostTxt = new JTextField();
        hostTxt.setPreferredSize(new Dimension(100,30));

        loginBtn = new JButton("Login!");
        loginBtn.setPreferredSize(new Dimension(90,30));
        loginBtn.addActionListener(new LoginBtnListener());


        panel.add(titleLbl);
        panel.add(userLbl);
        panel.add(userTxt);
        panel.add(passLbl);
        panel.add(passTxt);
        panel.add(hostLbl);
        panel.add(hostTxt);
        panel.add(portLbl);
        panel.add(portTxt);
        panel.add(ipLbl);
        panel.add(ipTxt);
        panel.add(loginBtn);

        frame.add(panel);

    }

    private class LoginBtnListener implements ActionListener
    {
        @SuppressWarnings("deprecation")
        public void actionPerformed(ActionEvent action)
        {
            //thinking this frame will close after ClientMenu's frame is open
            ClientModule client = new ClientModule();
            client.setVisible(false);

            ClientMenu menu = new ClientMenu();
            menu.setVisible(true);
        }
    }

    public void run()
    {
        frame.pack();
        frame.setVisible(true);
    }
}

ClientMenu.java

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

public class ClientMenu extends JFrame{

    JFrame frame;
    JPanel panel;
    JLabel titleLbl;
    JButton sendBtn,receiveBtn,logoutBtn;

    public ClientMenu()
    {
        frame = new JFrame("Drawing Message System(DMS)");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setResizable(false);

        panel = new JPanel();
        panel.setLayout(new FlowLayout());
        panel.setPreferredSize(new Dimension(500,500));

        titleLbl = new JLabel("Main Menu");
        titleLbl.setFont(new Font("Rockwell Condensed",Font.BOLD,28));

        sendBtn = new JButton("Send a Drawing");
        sendBtn.setPreferredSize(new Dimension(100,30));

        receiveBtn = new JButton("Receive a Drawing");
        receiveBtn.setPreferredSize(new Dimension(100,30));

        logoutBtn = new JButton("Logout");
        logoutBtn.setPreferredSize(new Dimension(100,30));
        logoutBtn.addActionListener(new LogoutBtnListener());

        panel.add(titleLbl);
        panel.add(sendBtn);
        panel.add(receiveBtn);
        panel.add(logoutBtn);

        frame.add(panel);
    }

    private class LogoutBtnListener implements ActionListener
    {
        //@SuppressWarnings("deprecation")
        public void actionPerformed(ActionEvent action)
        {
            ClientModule client = new ClientModule();
            client.setVisible(true);

            ClientMenu menu = new ClientMenu();
            menu.setVisible(false);
        }
    }

    public static void main(String[] args)
    {
        new ClientMenu().run();
    }

    public void run()
    {
        frame.pack();
        frame.setVisible(true);
    }

}

I'm not sure if i'm missing something, or coded something wrong, or something else. I've already searched and tried.. any help and understanding is appreciated (:

What would happen if you call `run()` from the constructor of your 2nd frame? — npinti, May 20 '15 at 08:37
ahh,,sorry.. if i click the button in ClientModule class, it should open the 2nd frame from ClientMenu class. But the Gui components are not shown in the 2nd frame.. — Preeyah, May 20 '15 at 08:39
and.. i'm not sure how to make the 1st frame(ClientModule) to be closed automatically after 2nd frame is opened.. — Preeyah, May 20 '15 at 08:39
@npinti the `run( )` method should display the frame which has the panel and the components — Preeyah, May 20 '15 at 08:41
Did you tried to directly run your 2nd frame to see if components are displayed ? — Kapcash, May 20 '15 at 08:44
Your code is a whole mess and you clearly do not understand how instantiation works in Java. You can try to add `menu.run()` to your listener. — Murat Karagöz, May 20 '15 at 08:45
To programmatically close a JFrame, refer to this [link](http://stackoverflow.com/questions/1234912/how-to-programmatically-close-a-jframe) — Kapcash, May 20 '15 at 08:46
@Kapcash yeah did directly run and the components are shown. — Preeyah, May 20 '15 at 08:48
`ClientModule client = new ClientModule();` this makes no sense in you buttons `ActionListener`, you should just use the instance of `ClientModule` which already have. Your `ClientMenu` class extends from `JFrame` BUT creates it's own instance of `JFrame` internally, which is causing no end of confusion and problems — MadProgrammer, May 20 '15 at 08:50
Take a look at [The Use of Multiple JFrames, Good/Bad Practice?](http://stackoverflow.com/q/9554636/418556) and instead may be use a `CardLayout` or dialog. See [How to Use CardLayout](http://docs.oracle.com/javase/tutorial/uiswing/layout/card.html) and [How to Make Dialogs](http://docs.oracle.com/javase/tutorial/uiswing/components/dialog.html) for more details — MadProgrammer, May 20 '15 at 08:51
I'd discourage you from extending directly from `JFrame` and I'm not sure why you need to implement `Runnable` — MadProgrammer, May 20 '15 at 08:52

score 2 · Accepted Answer · answered May 20 '15 at 08:56

I managed to get the second frame displayed (including its contents) by adding a call to the run() method:

        ClientMenu menu = new ClientMenu();
        menu.setVisible(true);  
        menu.run();

That being said, there are quite some problems with your code:

You have a main method in each of your classes. You should have only 1 main method per application. Since ClientModule seems to be the first Frame you want to have opened, your might want to keep the main method there and remove the one in the other class.
You have a run() method in each class. Personally, I tend to avoid naming methods like this, since it might cause confusion with the run() method which needs to be overridden when dealing with threads. You are clearly attempting to do some multi threading in your ClientModule, but will not work. Please look into this concurrency tutorial to better understand threads. You should also understand that you should never call run() yourself. The tutorial should make that clear.
Swing applications are started a little bit differently that other applications. Please refer to this tutorial for more information.
You have both your classes extend JFrame but then, provide your own. This results in other JFrames being created, which is what happened in my case (I get 2 JFrames per instantiation). If you want your class to behave like a JFrame, consider extending it, if you want to use a JFrame, then compose your class of one, not both (at least not in this case).
Lastly, to get rid of the previous JFrame you could call dispose() on the it. That being said, the approach usually is to use the Card Layout. This would allow you to have 1 frame with multiple content.

Sorry for the long post, but please consider re factoring as per the above prior to continuing.

score 1 · Answer 2 · answered May 20 '15 at 09:04

1

You can use the setVisible property to 'true' or 'false'.

answered May 20 '15 at 09:04

Swafvan Muhammed

41
4

Java GUI - JButton opens another frame from another class

2 Answers2