Question

I have a JList with a key listener to make it easy for the user to delete an item from the list. On windows, it works fine. You hit the delete key and the item is removed. On mac, the program does not respond to the delete key. I am using KeyEvent.VK_DELETE and I thought this was a platform neutral way of detecting special keys. Is there a different way I should be detecting the key press on the Mac?

    studentJList.setModel(studentListModel);  // a custom model I wrote
    studentJList.addKeyListener(new KeyListener() {
        @Override
        public void keyPressed(KeyEvent e) {
            if (e.getKeyCode() == KeyEvent.VK_DELETE) {
                studentListModel.remove(studentJList.getSelectedIndex());
                studentJList.revalidate();
            }
        }

        @Override
        public void keyReleased(KeyEvent e) { }

        @Override
        public void keyTyped(KeyEvent e) { }
    });

Answer 1

for example

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

public class ListDemo extends JPanel {

    private static final long serialVersionUID = 1L;
    private JFrame frame = new JFrame("ListDemo");
    private JList list;
    private DefaultListModel listModel;

    public ListDemo() {
        super(new BorderLayout());
        listModel = new DefaultListModel();
        listModel.addElement("Jane Doe");
        listModel.addElement("John Smith");
        listModel.addElement("Kathy Green");
        list = new JList(listModel);
        list.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
        list.setSelectedIndex(0);
        list.setVisibleRowCount(5);
        JScrollPane listScrollPane = new JScrollPane(list);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.add(listScrollPane, BorderLayout.CENTER);
        frame.pack();
        frame.setVisible(true);
        setKeyBindings();
    }

    private void setKeyBindings() {
        list.getInputMap(JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT)
                .put(KeyStroke.getKeyStroke("DELETE"), "clickDelete");
        list.getActionMap().put("clickDelete", new AbstractAction() {

            private static final long serialVersionUID = 1L;

            @Override
            public void actionPerformed(ActionEvent e) {
                int index = list.getSelectedIndex();
                if (index > -1) {
                    listModel.remove(index);
                }
            }
        });
    }

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

            public void run() {
                ListDemo listDemo = new ListDemo();
            }
        });
    }
}