Create a list of entries and make each entry clickable

Question

I am trying to create an UI which has two panes.

In the left pane I display the list of files and right pane displays the contents.

Now, I want list of files in the left pane to look as a normal list. But when I click an entry in this list, the contents of the particular file should be displayed in the right pane.

How can I achieve this using Swing?

Answer 1

Here I have done a short example, with the help of JList on the left and JTextArea on right. I have used ListSelectionListener to get the item list change. Use a LayoutManager as per your convenience.

import javax.swing.*;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;

public class JListTest {

    private JList jList1;
    private JPanel jPanel1;
    private JTextArea jTextArea1;

    public JListTest() {
        initComponents();
    }

    private void initComponents() {
        JFrame f = new JFrame();
        jPanel1 = new JPanel();
        jList1 = new JList();
        jTextArea1 = new JTextArea();

        jList1.setModel(new AbstractListModel() {

            String[] strings = {"Item 1", "Item 2"};

            @Override
            public int getSize() {
                return strings.length;
            }

            @Override
            public Object getElementAt(int i) {
                return strings[i];
            }
        });
        jList1.addListSelectionListener(new ListSelectionListener() {

            @Override
            public void valueChanged(ListSelectionEvent evt) {
                jList1ValueChanged(evt);
            }
        });

        jTextArea1.setColumns(20);
        jTextArea1.setRows(5);

        jPanel1.add(jList1);
        jPanel1.add(jTextArea1);
         f.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        f.add(jPanel1);
        f.pack();
        f.setVisible(true);
    }

    private void jList1ValueChanged(javax.swing.event.ListSelectionEvent evt) {
        //set text on right here
        String s = (String) jList1.getSelectedValue();
        if (s.equals("Item 1")) {
            jTextArea1.setText("You clicked on list 1");
        }
        if (s.equals("Item 2")) {
            jTextArea1.setText("You clicked on list 2");
        }
    }

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

            @Override
            public void run() {
                new JListTest();
            }
        });
    }
}

Answer 2

Check out this tutorial. It explains how to use lists in Swing, including event handlers that are necessary to register for click events.

Answer 3

You might want to look at this JTree example.

Answer 4

first off, you have not even tried yet, right? Swing does almost everything input related with listeneres. Check out the mouse listener, or adjust the awnser giving below

https://stackoverflow.com/a/4344762/258418

For completness I quote it here:

String[] items = {"A", "B", "C", "D"};
JList list = new JList(items);

list.addMouseListener(new MouseAdapter() {
    public void mouseClicked(MouseEvent evt) {
        JList list = (JList)evt.getSource();
        if (evt.getClickCount() == 2) {
            int index = list.locationToIndex(evt.getPoint());
        } else if (evt.getClickCount() == 3) {   // Triple-click
            int index = list.locationToIndex(evt.getPoint());

        }
    }
});

I am sure you can make it take single clicks as well,... if not write a comment

Answer 5

Some examples for reference:

• FileBrowser uses a JTree on the left and nested detail panels on the right.

• ImageDisplay embeds a custom JFileChooser on the left and displays a scrollable image on the right.

• CheckTable shows a JTable on the left and a DisplayPanel on the right.

Answer 6

Use JList.addListSelectionListener(ListSelectionListener).

See How to Write a List Selection Listener for more examples.