Question

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

class Menu extends JFrame implements ActionListener{    

    // Create the components and global variables
    JButton newGameButton = new JButton("New Game");
    JButton instructionGameButton = new JButton("Instructions");
    JButton exitButton = new JButton("Exit");
    JLabel mylabel = new JLabel("Welcome to Blackjack");

    public Menu()
    {

        // Create the window
        super("ThreeButtons");
        setSize(300,100);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setVisible(true);

        //Creating the container for the components and set the layout
        Container content = getContentPane();
        FlowLayout layout = new FlowLayout();
        content.setLayout(layout);

        //Adding the event listener
        newGameButton.addActionListener(this);
        instructionGameButton.addActionListener(this);
        exitButton.addActionListener(this);

        //Adding of components
        content.add(mylabel);
        content.add(newGameButton);
        content.add(instructionGameButton);
        content.add(exitButton);


        setContentPane(content);

    }

    //Add the event handler
    public void actionPerformed(ActionEvent event)
    {
    if (event.getActionCommand()=="New Game")
    new lol4();

    if (event.getActionCommand()=="Instructions")
    //new Instructions();

    if (event.getActionCommand()=="Quit ?")
    System.exit(0);


    }


    public static void main (String[] args)
    {
        //Create an instance of my class
    new Menu();
    }

}

Exit does not seem to work

Answer 1

I never liked the “switch-board” action listeners where the listener tries to do everything and risks doing nothing due to hard to fix bugs. Better I think to use anonymous inner classes either to hold simple code themselves, or if more complex to route code to other methods, or if still more complex, to call a Controller’s method.

For example:

  newGameButton.addActionListener(new ActionListener() {
     public void actionPerformed(ActionEvent e) {
        newGameActionPerformed(); // delegate this to a class method
     }
  });

  instructionGameButton.addActionListener(new ActionListener() {
     public void actionPerformed(ActionEvent e) {
        // call a controller object's methods
        if (myController != null) {
           myController.instructionGameAction();
        }
     }
  });

  exitButton.addActionListener(new ActionListener() {
     public void actionPerformed(ActionEvent e) {
        Menu.this.dispose(); // simple code can be called in-line
     }
  });

and elsewhere in the class:

   private void newGameActionPerformed() {
      // TODO add some code here!
   }

   public void setController(MyController myController) {
      this.myController = myController;
   }