Main.java Source code

Introduction

Here is the source code for Main.java

Source

import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JPanel;

public class Main extends JPanel {

    public Main() {
        JComboBox<String> cb = new JComboBox<>(new String[] { "a", "m", "b", "c", "v" });
        cb.setSelectedIndex(-1);

        JButton button = new JButton("Print Selection");
        button.addActionListener(e -> {
            if (cb.getSelectedIndex() != -1)
                System.out.println(cb.getSelectedItem());
            else
                System.out.println("Not selected");
        });

        add(cb);
        add(button);
    }

    public static void main(String[] args) {
        JFrame f = new JFrame();
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.add(new Main());
        f.pack();
        f.setSize(400, 300);
        f.setVisible(true);
    }
}