Question

I am trying to make a GUI for a game. First off I load a welcome screen in a jFrame. They enter details and if the details are correct it should load the next screen which is in a different class. It checks the details correctly and opens the new window but does not display it, it is just black? I’m not sure if it is my computer or my code?
This is the code for the second window:

import java.net.*;
import java.io.*;
import java.util.*;

public class ClientGUI extends javax.swing.JFrame {

/**
 * Creates new form ClientGUI
 */
private BufferedWriter writer;
public ClientGUI() {
     /*
     * Set the Nimbus look and feel
     */
    //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
    /*
     * If Nimbus (introduced in Java SE 6) is not available, stay with the
     * default look and feel. For details see
     * http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
     */
    try {
        for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
            if ("Nimbus".equals(info.getName())) {
                javax.swing.UIManager.setLookAndFeel(info.getClassName());
                break;
            }
        }
    } catch (ClassNotFoundException ex) {
        java.util.logging.Logger.getLogger(ClientGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (InstantiationException ex) {
        java.util.logging.Logger.getLogger(ClientGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (IllegalAccessException ex) {
        java.util.logging.Logger.getLogger(ClientGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (javax.swing.UnsupportedLookAndFeelException ex) {
        java.util.logging.Logger.getLogger(ClientGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    }
    //</editor-fold>

    /*
     * Create and display the form
     */
    setVisible(true);
    initComponents();
}

/**
 * This method is called from within the constructor to initialise the form.
 * WARNING: Do NOT modify this code. The content of this method is always
 * regenerated by the Form Editor.
 */
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">

    jButton1.setText("Move N");
    jButton1.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            jButton1ActionPerformed(evt);
        }
    });

    jButton2.setText("Move E");
    jButton2.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            jButton2ActionPerformed(evt);
        }
    });

    jButton3.setText("Move S");
    jButton3.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            jButton3ActionPerformed(evt);
        }
    });

    jButton4.setText("Move W");
    jButton4.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            jButton4ActionPerformed(evt);
        }
    });

    jButton5.setText("Pickup");
    jButton5.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            jButton5ActionPerformed(evt);
        }
    });

    jButton6.setText("Quit");
    jButton6.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            jButton6ActionPerformed(evt);
        }
    });



private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         

    try{
        writer.write("Move N");
        writer.newLine();
        writer.flush();
    }
    catch(Exception e){
            System.out.println("error");
    }

}                                        

private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {                                         
   try{
        writer.write("Move E");
        writer.newLine();
        writer.flush();
    }
    catch(Exception e){
            System.out.println("error");
    }
}                                        

private void jButton3ActionPerformed(java.awt.event.ActionEvent evt) {                                         
    try{
        writer.write("Move S");
        writer.newLine();
        writer.flush();
    }
    catch(Exception e){
            System.out.println("error");
    }
}                                        

private void jButton4ActionPerformed(java.awt.event.ActionEvent evt) {                                         
    try{
        writer.write("Move W");
        writer.newLine();
        writer.flush();
    }
    catch(Exception e){
            System.out.println("error");
    }
}                                        

private void jButton5ActionPerformed(java.awt.event.ActionEvent evt) {                                         
    try{
        writer.write("PICKUP");
        writer.newLine();
        writer.flush();
    }
    catch(Exception e){
            System.out.println("error");
    }
}                                        

private void jButton6ActionPerformed(java.awt.event.ActionEvent evt) {                                         
    setVisible(false);
}                                        

/**
 * @param args the command line arguments
 */
public void run(){
try {
        final Socket server = new Socket("localhost", 30000);
    //Creates the socket to be used, has to be final because of innerclass
    InputStream in = server.getInputStream();
    OutputStream out = server.getOutputStream();
    //Creates the input and output streams

    BufferedReader stdin = new BufferedReader(new InputStreamReader(System.in));
    //Creates the reader to read what the client inputs
    final BufferedReader reader = new BufferedReader(new InputStreamReader(in));
    //Creates the reader to read what the server writes to the client, has to be final as used in innerclass
    writer = new BufferedWriter(new OutputStreamWriter(out));
    //Creates the writer so the client can write on the commandline

    Thread serverThread = new Thread(){
        //Modifies the Thread class
        public void run(){
        boolean quit = false;
        while (!quit){
            String line = "";
            try{
            line = reader.readLine();
            //Tries to read what the server has sent
            }
            catch(IOException e){
            System.out.println("Error" + e.getMessage());
            quit = true;
            //If it is unable to read what the server sent, it quits the loop
            }
            if (line != "null"){
                System.out.println(line);
            //So long as the line sent is not "null" it prints the line to the client
            }
        }
        }           
    };
    serverThread.start();
    //Starts the Thread

    String input = stdin.readLine();
    while (input != null) {
    writer.write(input);
    writer.newLine();
    writer.flush();
    input = stdin.readLine();
    //Reads what the client writes
    }
    System.exit(1);
    server.close();
} 
catch (IOException e) {
    System.out.println("error" + e.getMessage());
    e.printStackTrace();
    //Catches any errors with reading and writing to and from the server
}
}

Plus some extra swing bits that netbeans does by default.
Any help would be appreciated, thanks.

Answer 1

Your problem may be here:

setVisible(true);
initComponents();

You should reverse the order of this:

initComponents();
setVisible(true);

Also, you appear to be doing Socket work. If so, hopefully you are taking care to do this in a background thread, and not in the main Swing event thread, the EDT.