如何将2个JList添加到一个JScrollPane中？

Question

Imagine a group of people with names and ages . I would like the user of my application to be able to scroll through and select members of this group by name , whilst displaying their ages to the right. So I essentially want two JLists added to one JScrollPane, with the two JLists scrolling in sync (scrolling down brings up both the next name and age). It's worth saying that the JList containing the ages needn't be selected as well as the name, the crucial point is that it must be synced up to scroll with the names.

I've tried a couple of ideas and have ended up with the following code:

public class Main {



    public static void main(String args[]) {
        Main main = new Main();
        main.go();
    }

    private void go() {

        String[] words = {"David", "Stephanie", "Mark", "Michelle", "Simon", "Rupert",
                "Mitchell", "Charles", "Owen"};
        String[] numbers = {"43","12","15","65","12","76","33","45","34"};

        JFrame frame = new JFrame();
        JPanel background = new JPanel();

        JList<String> listOne = new JList<String>(words);
        JList<String> listTwo = new JList<String>(numbers);

        JPanel listPanel = new JPanel();
        listPanel.add(listOne);
        listPanel.add(listTwo);

        JScrollPane scrollPane = new JScrollPane(listPanel);

        background.add(scrollPane);
        frame.getContentPane().add(background);
        frame.setVisible(true);
        frame.pack();
        frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    }

}

If anyone can suggest a better approach then feel free but otherwise my question is simply how can I implement said feature?

Thanks in advance!

Answer 1

So I essentially want two JLists added to one JScrollPane, with the two JLists scrolling in sync (scrolling down brings up both the next name and age).

Yours is an XY Problem as you don't really want this. Instead you should use the component built to display multi-columned tabular data -- a JTable. I think that part of your problem is with the faulty parallel array structure of your data. Instead create a class to hold a String and number and then create a collection or array of items of this class.

eg,

import javax.swing.*;
import javax.swing.table.DefaultTableModel;

public class Main2 extends JPanel {
   private static final String[] COLUMNS = {"Name", "Age"};
   private Person[] people = {
         new Person("David", 43),
         new Person("Stephanie", 12),
         new Person("Mark", 15),
         new Person("Michelle", 65)
   };

   public Main2() {
      DefaultTableModel tableModel = new DefaultTableModel(COLUMNS, 0);
      for (Person person : people) {
         Object[] row = {person.getName(), person.getAge()};
         tableModel.addRow(row);
      }

      add(new JScrollPane(new JTable(tableModel)));
   }

   private static void createAndShowGui() {
      Main2 mainPanel = new Main2();

      JFrame frame = new JFrame("Main2");
      frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
      frame.getContentPane().add(mainPanel);
      frame.pack();
      frame.setLocationByPlatform(true);
      frame.setVisible(true);
   }

   public static void main(String[] args) {
      SwingUtilities.invokeLater(new Runnable() {
         public void run() {
            createAndShowGui();
         }
      });
   }
}

class Person {
   private String name;
   private int age; // although Date for birthdate would be better
   public Person(String name, int age) {
      this.name = name;
      this.age = age;
   }
   public String getName() {
      return name;
   }
   public int getAge() {
      return age;
   }


}