title: JButton in JFrame does not work
body: <p>I'm currently working on a simple project in Netbeans, getting used to the JFrame Form. I created a couple of JFrames and I want to jump through them by pressing buttons, but whenever I press a button nothing happens.</p>
  
  <p>This is my code</p>
  
  <pre><code>public class MainLogIn extends javax.swing.JFrame {
  
  /**
   * Creates new form MainLogIn
   */
  
  //testdata
  private String[] dummy_data = {"user1:parola1", "user2:parola2"};
  
  public MainLogIn() {
      initComponents();
  
      LogIn = new JButton();
      signUp = new JButton();
      username = new JTextField();
      password = new JPasswordField();
  
      wrong = new JLabel();
      wrong.setVisible(false);
  }
  
  /**
   * This method is called from within the constructor to initialize the form.
   * WARNING: Do NOT modify this code. The content of this method is always
   * regenerated by the Form Editor.
   */
  @SuppressWarnings("unchecked")
  // &lt;editor-fold defaultstate="collapsed" desc="Generated Code"&gt;                          
  private void initComponents() {
  
      jLabel1 = new javax.swing.JLabel();
      jLabel2 = new javax.swing.JLabel();
      username = new javax.swing.JTextField();
      password = new javax.swing.JPasswordField();
      LogIn = new javax.swing.JButton();
      signUp = new javax.swing.JButton();
      wrong = new javax.swing.JLabel();
  
      setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
  
      jLabel1.setText("Username:");
  
      jLabel2.setText("Password:");
  
      LogIn.setText("LogIn");
      LogIn.addActionListener(new java.awt.event.ActionListener() {
          public void actionPerformed(java.awt.event.ActionEvent evt) {
              LogInActionPerformed(evt);
          }
      });
  
      signUp.setText("SignUp");
      signUp.addActionListener(new java.awt.event.ActionListener() {
          public void actionPerformed(java.awt.event.ActionEvent evt) {
              signUpActionPerformed(evt);
          }
      });
  
      wrong.setText("Wrong Username And Password");
      wrong.setVisible(false);
  
      javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
      getContentPane().setLayout(layout);
      layout.setHorizontalGroup(
          layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
          .addGroup(layout.createSequentialGroup()
              .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                  .addGroup(layout.createSequentialGroup()
                      .addGap(16, 16, 16)
                      .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
                          .addComponent(jLabel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                          .addComponent(jLabel2, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
                      .addGap(31, 31, 31)
                      .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
                          .addComponent(username, javax.swing.GroupLayout.DEFAULT_SIZE, 120, Short.MAX_VALUE)
                          .addComponent(password)))
                  .addGroup(layout.createSequentialGroup()
                      .addGap(28, 28, 28)
                      .addComponent(LogIn)
                      .addGap(95, 95, 95)
                      .addComponent(signUp))
                  .addGroup(layout.createSequentialGroup()
                      .addGap(60, 60, 60)
                      .addComponent(wrong)))
              .addContainerGap(146, Short.MAX_VALUE))
      );
      layout.setVerticalGroup(
          layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
          .addGroup(layout.createSequentialGroup()
              .addGap(51, 51, 51)
              .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING)
                  .addComponent(username, javax.swing.GroupLayout.PREFERRED_SIZE, 35, javax.swing.GroupLayout.PREFERRED_SIZE)
                  .addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 27, javax.swing.GroupLayout.PREFERRED_SIZE))
              .addGap(18, 18, 18)
              .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                  .addComponent(jLabel2)
                  .addComponent(password, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
              .addGap(52, 52, 52)
              .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                  .addComponent(LogIn)
                  .addComponent(signUp))
              .addGap(26, 26, 26)
              .addComponent(wrong)
              .addContainerGap(48, Short.MAX_VALUE))
      );
  
      pack();
  }// &lt;/editor-fold&gt;                        
  
  private boolean isPasswordValid(String password)
  {
      if(password.length()&gt;8)
          return true;
      else
          return false;
  }
  
  private boolean loginAttempt(String user, String pass){
  
      String usertext, passtext;
  
      //get username and password
      usertext = user;
      passtext = pass;
  
      //check username
      if(usertext == null)
      {
          username.setText("Please add username");
      }
      if(passtext == null)
      {
          password.setText("Please add password");
      }
      else
          if(isPasswordValid(passtext) == false)
              password.setText("Password too short");
  
      //check for good data among dummy_data
      for(String credentials:dummy_data)
      {
          String[] user_pass = credentials.split(":");
          if(user_pass[0].equals(usertext) &amp;&amp;
             user_pass[1].equals(passtext))
              {
                  return true;
              }
      }
  
      return false;
  }
  
  
  private void LogInActionPerformed(java.awt.event.ActionEvent evt) {                                      
      // TODO add your handling code here:
      String usertext, passtext;
      usertext = username.getText().toString();
      passtext = password.getText().toString();
      if(loginAttempt(usertext,passtext) == true)
      { 
          LogIn.addActionListener(new ActionListener()
          {
              @Override
              public void actionPerformed(ActionEvent ae) {
                  WelcomeToTheServer view = new WelcomeToTheServer();
                  view.setVisible(true);
                  throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
              }
  
          });
      }
      else
      {
          wrong.setVisible(true);
      }
  
  }                                     
  
  private void signUpActionPerformed(java.awt.event.ActionEvent evt) {                                       
      // start NewUser JFrame
       signUp.addActionListener(new ActionListener()
          {
              @Override
              public void actionPerformed(ActionEvent ae) {
                  NewUser new_userjframe = new NewUser();
                  new_userjframe.setVisible(true);
                  throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
              }
  
          });
  }                                      
  
  /**
   * @param args the command line arguments
   */
  public static void main(String args[]) {
      /* Set the Nimbus look and feel */
      //&lt;editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) "&gt;
      /* 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(MainLogIn.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
      } catch (InstantiationException ex) {
          java.util.logging.Logger.getLogger(MainLogIn.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
      } catch (IllegalAccessException ex) {
          java.util.logging.Logger.getLogger(MainLogIn.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
      } catch (javax.swing.UnsupportedLookAndFeelException ex) {
          java.util.logging.Logger.getLogger(MainLogIn.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
      }
      //&lt;/editor-fold&gt;
  
      /* Create and display the form */
      java.awt.EventQueue.invokeLater(new Runnable() {
          public void run() {
              new MainLogIn().setVisible(true);
          }
      });
  }
  
  // Variables declaration - do not modify                     
  private javax.swing.JButton LogIn;
  private javax.swing.JLabel jLabel1;
  private javax.swing.JLabel jLabel2;
  private javax.swing.JPasswordField password;
  private javax.swing.JButton signUp;
  private javax.swing.JTextField username;
  private javax.swing.JLabel wrong;
  // End of variables declaration                   
  </code></pre>
  
  <p>}</p>
  
  <p>when I try</p>
  
  <pre><code>LogIn.addActionListener(new ActionListener()
          {
              @Override
              public void actionPerformed(ActionEvent ae) {
                  WelcomeToTheServer view = new WelcomeToTheServer();
                  view.setVisible(true);
                  throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
              }
  
          });
  </code></pre>
  
  <p>nothig happens. Did I write the ActionListener wrong?</p>
  
  <p>Thank you</p>