Java Action listener not outputting results

Question

I am learning Java in school, and we are learning to make GUI's.

Toady we are doing Menubars and such, which I think I understand, and adding menuitems, which I understand. But when I want them to do something when a user clicks on them. I am lost.

Here is my code of the UI:

package UserInterface;

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

/**
 *
 * @author Jesse
 */
public class AirlineReservation {

    private JFrame frame;
    private JMenuBar menuBar;
    private JMenu fileMenu;
    private JMenuItem addAirport;
    private JMenuItem addAirline;
    private JMenuItem addFlight;
    private JMenuItem exit;
    private JMenu aboutMenu;
    private JMenuItem bookFlight;
    private JMenuItem aboutInfo;
    private JMenu bookMenu;

    public AirlineReservation() {
        initComponents();
    }

    private void initComponents() {
        frame = new JFrame("Airline Reservation ");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setSize(300, 300);
        frame.setVisible(true);

        // Initializing the JMenuBar
        menuBar = new JMenuBar();
        frame.setJMenuBar(menuBar);
        // Initializing menu items
        addAirport = new JMenuItem("Add Airport");
        addAirline = new JMenuItem("Add Airline");
        addFlight = new JMenuItem("Add Flight");
        exit = new JMenuItem("Exit");
        // Initializing the JMenu and adding JMenuItems
        fileMenu = new JMenu("File");
        fileMenu.setMnemonic('F');
        fileMenu.add(addAirport);
        fileMenu.add(addAirline);
        fileMenu.add(addFlight);
        fileMenu.add(exit);
        menuBar.add(fileMenu);
        fileMenu.addActionListener(new FileMenuAction());

        //initializing the Jmenu and adding JMenuItems (bookFlight)
        bookFlight = new JMenuItem("Flight Reservation");
        bookMenu = new JMenu("Book");
        bookMenu.setMnemonic('B');
        bookMenu.add(bookFlight);
        bookMenu.addActionListener(new BookMenuAction());
        menuBar.add(bookMenu);

        aboutInfo = new JMenuItem("dhdhd");
        aboutMenu = new JMenu("About");
        aboutMenu.add(aboutInfo);
        aboutMenu.addActionListener(new AboutMenuAction());
        menuBar.add(aboutInfo);
    }

    private class FileMenuAction implements ActionListener {

        @Override
        public void actionPerformed(ActionEvent e) {
            if (e.getActionCommand() == "Add Airport") {
                System.out.println("Add Airport Clicked");
            } else if (e.getActionCommand() == "Add Airline") {
                System.out.println("Add Airline Clicked");

            } else if (e.getActionCommand() == "Add Flight") {
                System.out.println("Add Flight Clicked");
            }
        }
    }

    private class BookMenuAction implements ActionListener {

        public void actionPerformed(ActionEvent e) {
            if (e.getActionCommand() == "sjsjsjs") {
                System.out.println("fjfhfhf");
            }
        }
    }

    private class AboutMenuAction implements ActionListener {

        public void actionPerformed(ActionEvent e) {}
    }
}

the problem is that when I click on a menuitems, it seems as if my actionlistener does not catch the click? It has to be a small logical error, and I can seem to put my finger on it :(

Use `equals()` not `==` to compare strings. – Martin Dinov Feb 22 '14 at 15:34 — Martin Dinov, Feb 22 '14 at 15:34

score 0 · Accepted Answer · answered Feb 22 '14 at 15:46

You never add any ActionListener to your menu items. So obviously, nothing happens when you click them.

On the other hand, you're adding a listener to each menu, but you shouldn't, because nothing should happen when clicking the menu (expect it should open itself, but it does that automatically).

The next steps will be

to avoid comparing strings with ==
to actually assign an action command to your menu items, since your listener uses that to know which item was clicked

I would suggest creating a single listener class for each item instead of using one listener class to handle several items.

I thought about that. I was following my professors examples. My professor only wants one inner class to handle the menu items. I would make multiple classes for each, but its what she wants, but it seems less organized. btw It works like a charm now. Thanks guys! — user3026473, Feb 22 '14 at 15:53

Java Action listener not outputting results

1 Answers1