Main.java Source code

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Here is the source code for Main.java

Source

import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;

import javax.swing.BorderFactory;
import javax.swing.BoxLayout;
import javax.swing.DefaultListModel;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.ListSelectionModel;

public class Main {
    public static void main(String[] args) {
        final DefaultListModel<String> model = new DefaultListModel<>();
        final JList<String> list = new JList<>(model);
        JFrame f = new JFrame();

        model.addElement("A");
        model.addElement("B");
        model.addElement("C");
        model.addElement("D");
        model.addElement("E");

        JPanel panel = new JPanel();
        panel.setLayout(new BoxLayout(panel, BoxLayout.X_AXIS));

        JPanel leftPanel = new JPanel();
        JPanel rightPanel = new JPanel();

        leftPanel.setLayout(new BorderLayout());
        rightPanel.setLayout(new BoxLayout(rightPanel, BoxLayout.Y_AXIS));

        list.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
        list.setBorder(BorderFactory.createEmptyBorder(2, 2, 2, 2));

        list.addMouseListener(new MouseAdapter() {
            public void mouseClicked(MouseEvent e) {
                if (e.getClickCount() == 2) {
                    int index = list.locationToIndex(e.getPoint());
                    Object item = model.getElementAt(index);
                    String text = JOptionPane.showInputDialog("Rename item", item);
                    String newitem = "";
                    if (text != null)
                        newitem = text.trim();
                    else
                        return;

                    if (!newitem.isEmpty()) {
                        model.remove(index);
                        model.add(index, newitem);
                        ListSelectionModel selmodel = list.getSelectionModel();
                        selmodel.setLeadSelectionIndex(index);
                    }
                }
            }
        });
        leftPanel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));

        leftPanel.add(new JScrollPane(list));

        JButton removeall = new JButton("Remove All");
        JButton add = new JButton("Add");
        JButton rename = new JButton("Rename");
        JButton delete = new JButton("Delete");

        add.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                String text = JOptionPane.showInputDialog("Add a new item");
                String item = null;

                if (text != null)
                    item = text.trim();
                else
                    return;

                if (!item.isEmpty())
                    model.addElement(item);
            }
        });

        delete.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent event) {
                ListSelectionModel selmodel = list.getSelectionModel();
                int index = selmodel.getMinSelectionIndex();
                if (index >= 0)
                    model.remove(index);
            }

        });

        rename.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                ListSelectionModel selmodel = list.getSelectionModel();
                int index = selmodel.getMinSelectionIndex();
                if (index == -1)
                    return;
                Object item = model.getElementAt(index);
                String text = JOptionPane.showInputDialog("Rename item", item);
                String newitem = null;

                if (text != null) {
                    newitem = text.trim();
                } else
                    return;

                if (!newitem.isEmpty()) {
                    model.remove(index);
                    model.add(index, newitem);
                }
            }
        });

        removeall.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                model.clear();
            }
        });

        rightPanel.add(add);
        rightPanel.add(rename);
        rightPanel.add(delete);
        rightPanel.add(removeall);

        rightPanel.setBorder(BorderFactory.createEmptyBorder(0, 0, 0, 20));

        panel.add(leftPanel);
        panel.add(rightPanel);

        f.add(panel);

        f.setSize(350, 250);
        f.setLocationRelativeTo(null);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.setVisible(true);

    }
}