Question

Two questions. First question is I’m trying to create a simple form that when you press a button, it adds a Person object to the ArrayList. However, since I am not used to GUIs, I tried creating one and am first just trying to get the user input from the JTextField, create an ActionListener object of the appropriate type, so once that works, then I can pass in all the JTextField inputs to create my Person object. Unfortunately, I am not getting any data when I type in something to the firstName JTextField and was wondering if someone could look at my code below.

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.util.List;
import java.util.ArrayList;

public class AddressBook
{
    public static void main(String[] args)
    {
        EventQueue.invokeLater(new Runnable()
        {
            public void run()
            {
                AddressBookFrame frame = new AddressBookFrame();
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

                JMenuBar menuBar = new JMenuBar();
                frame.setJMenuBar(menuBar);

                JMenu fileMenu = new JMenu("File");
                JMenuItem openItem = new JMenuItem("Open");
                JMenuItem saveItem = new JMenuItem("Save");
                JMenuItem saveAsItem = new JMenuItem("Save As");
                JMenuItem printItem = new JMenuItem("Print");
                JMenuItem exitItem = new JMenuItem("Exit");
                fileMenu.add(openItem);
                fileMenu.add(saveItem);
                fileMenu.add(saveAsItem);
                fileMenu.add(printItem);
                fileMenu.add(exitItem);
                menuBar.add(fileMenu);

                JMenu editMenu = new JMenu("Edit");
                JMenuItem newItem = new JMenuItem("New");
                JMenuItem editItem = new JMenuItem("Edit");
                JMenuItem deleteItem = new JMenuItem("Delete");
                JMenuItem findItem = new JMenuItem("Find");
                JMenuItem firstItem = new JMenuItem("First");
                JMenuItem previousItem = new JMenuItem("Previous");
                JMenuItem nextItem = new JMenuItem("Next");
                JMenuItem lastItem = new JMenuItem("Last");
                editMenu.add(newItem);
                editMenu.add(editItem);
                editMenu.add(deleteItem);
                editMenu.add(findItem);
                editMenu.add(firstItem);
                editMenu.add(previousItem);
                editMenu.add(nextItem);
                editMenu.add(lastItem);
                menuBar.add(editMenu);

                JMenu helpMenu = new JMenu("Help");
                JMenuItem documentationItem = new JMenuItem("Documentation");
                JMenuItem aboutItem = new JMenuItem("About");
                helpMenu.add(documentationItem);
                helpMenu.add(aboutItem);

                menuBar.add(helpMenu);

                frame.setVisible(true);

            }
        });
    }
}

class AddressBookFrame extends JFrame
{
    public AddressBookFrame() 
    {
        setLayout(new BorderLayout());
        setTitle("Address Book");
        setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);
        AddressBookToolBar toolBar = new AddressBookToolBar();
        add(toolBar, BorderLayout.NORTH);
        AddressBookStatusBar aStatusBar = new AddressBookStatusBar("5");
        add(aStatusBar, BorderLayout.SOUTH);
        AddressBookForm form = new AddressBookForm();
        add(form, BorderLayout.CENTER);
    }
    public static final int DEFAULT_WIDTH = 500;
    public static final int DEFAULT_HEIGHT = 500;

}

/* Create toolbar buttons and add buttons to toolbar */
class AddressBookToolBar extends JPanel
{
    public AddressBookToolBar()
    {
        setLayout(new FlowLayout(FlowLayout.LEFT));
        JToolBar bar = new JToolBar();
        JButton newButton = new JButton("New");
        JButton editButton = new JButton("Edit");
        JButton deleteButton = new JButton("Delete");
        JButton findButton = new JButton("Find");
        JButton firstButton = new JButton("First");
        JButton previousButton = new JButton("Previous");
        JButton nextButton = new JButton("Next");
        JButton lastButton = new JButton("Last");
        bar.add(newButton);
        bar.add(editButton);
        bar.add(deleteButton);
        bar.add(findButton);
        bar.add(firstButton);
        bar.add(previousButton);
        bar.add(nextButton);
        bar.add(lastButton);
        add(bar);
    }
}

/* Creates the status bar string */
class AddressBookStatusBar extends JPanel
{
    public AddressBookStatusBar(String statusBarString)
    {
        setLayout(new FlowLayout(FlowLayout.LEFT));
        this.statusBarString = new JLabel("Total number of people: " + statusBarString);
        add(this.statusBarString);
    }
    private JLabel statusBarString;
    private int totalContacts;
}

class AddressBookForm extends JPanel
{
    public AddressBookForm()
    {   
        this.setLayout(new GridLayout(2, 1));
        JPanel formPanel = new JPanel();
        formPanel.setLayout(new GridLayout(4, 2));
        JTextField firstName = new JTextField(20);
        JTextField lastName = new JTextField(20);
        JTextField telephone = new JTextField(20);
        JTextField email = new JTextField(20);
        JLabel firstNameLabel = new JLabel("First Name: ", JLabel.LEFT);
        formPanel.add(firstNameLabel);
        formPanel.add(firstName);
        JLabel lastNameLabel = new JLabel("Last Name: ", JLabel.LEFT); 
        formPanel.add(lastNameLabel);
        formPanel.add(lastName);
        JLabel telephoneLabel = new JLabel("Telephone: ", JLabel.LEFT);
        formPanel.add(telephoneLabel);
        formPanel.add(telephone);
        JLabel emailLabel = new JLabel("Email: ", JLabel.LEFT);
        formPanel.add(emailLabel);
        formPanel.add(email);
        add(formPanel);

        JPanel buttonPanel = new JPanel();
        JButton insertButton = new JButton("Insert");
        JButton displayButton = new JButton("Display");

        // create button actions
        AddressBookManager insertAction = new AddressBookManager(firstName.getText());
        insertButton.addActionListener(insertAction);
        buttonPanel.add(insertButton);
        buttonPanel.add(displayButton);
        add(buttonPanel);
    }

    private List<Person> addressList = new ArrayList<Person>();

    private class AddressBookManager implements ActionListener
    {
        public AddressBookManager(String text)
        {
//          addressList.add(
            setName(text);
            System.out.println("Test" + text);
        }

        public void actionPerformed(ActionEvent e)
        {
            System.out.println("Hello" + name);
        }

        public void setName(String name)
        {
            this.name = name;
        }

        private String name;
    }

}

Second question is, how do I make my form not take up the whole center space. I don’t like the stretch look and was hoping the JTextFields could be just one line long, not a big box. Same thing with the buttons. Any thoughts? Thanks.

Answer 1

I am not getting any data when I type in something to the firstName JTextField.

You’re feeding AddressBookManager an empty string. As an expedient, let it see the fields of interest in the parent, AddressBookForm. Addendum: As your application evolves, consider the organizational benefits described in How to Use Actions.

class AddressBookForm extends JPanel {
    JTextField firstName = new JTextField(20);
    JTextField lastName = new JTextField(20);
    JTextField telephone = new JTextField(20);
    JTextField email = new JTextField(20);

    public AddressBookForm() {
    ...
    }

    private class Person { ... }

    private List<Person> addressList = new ArrayList<Person>();

    private class AddressBookManager implements ActionListener {

        @Override
        public void actionPerformed(ActionEvent e) {
            addressList.add(new Person(...));
            System.out.println("Hello, " + firstName.getText());
        }

        public void setName(String name) {
            firstName.setText(name);
        }
    }
}

How do I make my form not take up the whole center space?

See Using Layout Managers. GridLayout ignores preferred sizes; I’d consider a nested BoxLayout.