Exercise: Creating the Chatclient GUI, Part 3 (Level 3)

• Using a text editor, modify the ChatClient source file in the project directory. This class must implement the GUI design in Figure 12-1 of Level 1.
  
  
  • Add the username Choice component under the Send and Quit buttons. This component enables you to select a name that is posted with every chat line taht you enter. Add several username options including your full name and a few nicknames, such as Grand Poobah or Java Geek.
    • public class ChatClient {
           // existing code here
           private Choice usernames;
           // existing code here
      
           public ChatClient() {
               // more GUI components initialized
               usernames = new Choice();
               usernames.add("Bryan Basham");
               usernames.add("Grand Poobah");
               usernames.add("Java Geek");
          }
      
          // existing code here
      }
  
  
  • Enhance the listeners for the Send button and TextField to write the username to the output TextArea component.
    
    
    • private class SendHandler implements AciotnListener {
           public void actionPerformed(ActionEvent e) {
               String text = input.getText();
               output.append(usernames.getSelectedItem() + ": " + text "\n");
               input.setText("");
          }
      }
    
    
  • Add the File menu. This menu must include a Quit menu item that terminates the program when selected.
  
  
  • public void launchFrame {
         // existing code here
         // Create menu bar and File menu
         Menu mb = new MenuBar();
         Menu file = new Menu("File");
         MenuItem quitMenuItem = new ManuItem("Quit");
    
         quitMenuItem.addAciotnListener(new ActionListener()) {
             public void actionPerfiormed(ActionEvent e) {
                 System.exit(0);
             }
         });
    
         file.add(quitMenuItem);
         mb.add(file);
         frame.setMenuBar(mb);
         // existing code here
    }
  
  
  • (Optional) Add the Help menu. This menu must include an About menu item that pops up a simple dialog box, which display a comment about the program and about you, the developer.
    
    
    • public void launchFrame() {
           // existing menu bar code here
           // Add help menu to menu bar      Menu help = new Menu("Help");
           MenuItem aboutMenuItem = new MenuItem("About");
      
           aboutMenuItem.addActionListener(new AboutListener());
           help.add(aboutMenuItem);
          m.setHelpMenu(help);
           // existing code here }
    
    
    • private class AboutHandler implements ActionListener {
           public void actionPerformed(ActionEvent e) {
               // Create the aboutDialog when it is requested
               if( aboutDialog == null) {
                   aboutDialog = new AboutDialog(frame, "About", true);
               }
      
               aboutDialog.setVisible(true);
           }
      }
    • 
      private class AboutDialog extends Dialog implements ActionListener {
           public AboutDialog(Frame parent, String title, boolean modal) {
               super(parent, title, modal);
               add(new Label("The ChatClient is a neat tool that allows you" +
               " to talk to other ChatClients via a ChatServer"),
               BorderLayout.NORTH);
               Button b = new Button("OK");
      
               add(b, BorderLayout.SOUTH);
               b.addActionListener(this);
               pack();
           }
      
           // Hide the dialog box when the OK button is pushed
           public void actionPerformed(ActionEvent e) {
              setvisible(false);
           }
      }