Main.java Source code

Introduction

Here is the source code for Main.java

Source

import java.awt.BorderLayout;
import java.awt.Frame;
import java.awt.event.WindowEvent;
import java.awt.event.WindowFocusListener;

import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.WindowConstants;

public class Main extends JDialog {
    public Main(final Frame owner) {
        super(owner);
        JPanel pnl = new JPanel(new BorderLayout());
        pnl.add(new JLabel("Click outside this dialog in the parent frame to close it"), BorderLayout.NORTH);
        JButton btn = new JButton("Click Me");
        btn.addActionListener(e -> JOptionPane.showMessageDialog(Main.this, "New Child Window"));
        pnl.add(btn, BorderLayout.CENTER);
        this.setContentPane(pnl);
        this.pack();
        this.setLocationRelativeTo(owner);
        this.setAlwaysOnTop(true);
        this.addWindowFocusListener(new WindowFocusListener() {
            public void windowGainedFocus(WindowEvent e) {
            }

            public void windowLostFocus(WindowEvent e) {
                if (SwingUtilities.isDescendingFrom(e.getOppositeWindow(), Main.this)) {
                    return;
                }
                Main.this.setVisible(false);
            }
        });
    }

    public static void main(String[] args) {
        JFrame parent = new JFrame();
        parent.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        parent.setSize(300, 300);
        parent.setVisible(true);
        Main dlg = new Main(parent);
        dlg.setVisible(true);
    }
}