GUI in java “go to previous/next” option?

Question

Is there a way to have an option to go the a previous message dialog box or a next one? I have a program where after all the input and math calculations is done, a message dialog box appears with the information for "Person 1" then you press ok and the one for "Person 2" appears. It would be nice if there could be an option to be able to navigate between the different dialog boxes. Here is the part of the program that prints the messages.

for (i = 0; i < NumEmployees; i++)    
{
    JOptionPane.showMessageDialog(null, 
            "Employee: " + names[i] + "\n" + 
            "ID: " + data[i][0] + "\n" + 
            "Hours worked: " + (data[i][1] + data[i][2]) + "\n" + 
            "Overtime: " + data[i][2] + "hours" + "\n" + 
            "Amount earned: " + payment[i]);    
}

Answer 1

Use Action "to separate functionality and state from a component." In the example below, the actions change the index and update() a JLabel from a List<String>. Your application might update a JTextArea from a List<Employee>.

package gui;

import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import javax.swing.AbstractAction;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;

/**
 * @see http://stackoverflow.com/a/20116944/230513
 */
public class PrevNext {

    private final List<String> list = new ArrayList<>(
        Arrays.asList("Alpher", "Bethe", "Gamow", "Dirac", "Einstein"));
    private int index = list.indexOf("Einstein");
    private final JLabel label = new JLabel(list.get(index), JLabel.CENTER);

    private void display() {
        JFrame f = new JFrame("PrevNext");
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.add(new JButton(new AbstractAction("<Prev") {

            @Override
            public void actionPerformed(ActionEvent e) {
                if (--index < 0) {
                    index = list.size() - 1;
                }
                update();
            }
        }), BorderLayout.LINE_START);
        f.add(label);
        f.add(new JButton(new AbstractAction("Next>") {

            @Override
            public void actionPerformed(ActionEvent e) {
                if (++index == list.size()) {
                    index = 0;
                }
                update();
            }
        }), BorderLayout.LINE_END);
        f.pack();
        f.setLocationRelativeTo(null);
        f.setVisible(true);
    }

    private void update() {
        label.setText(list.get(index));
    }

    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {

            @Override
            public void run() {
                new PrevNext().display();
            }
        });
    }
}