// David Greenstein
// March 12, 2013
// HelloSwing.java
// A JFrame that shows a button that says
// "Click Me!".  When the button is clicked, an informational
// dialog box appears to say Hello from Swing.

import javax.swing.*;    // Swing GUI classes are defined here.
import java.awt.event.*; // Event handling class are defined here.

public class HelloSwing implements ActionListener 
{

	JFrame frame;
	
	public static void main(String[] args) 
	{
		HelloSwing hs = new HelloSwing();
		hs.Run();
	}

	public void Run() 
	{
		frame = new JFrame("HelloSwing");
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		
        // This method is called by the system before the applet
        // appears.  It is used here to create the button and add
        // it to the "content pane" of the JApplet.  The applet
        // is also registered as an ActionListener for the button.

        JButton bttn = new JButton("Click Here, MV Java Students!");
        bttn.addActionListener(this);
        frame.add(bttn);
		
		frame.setSize(500, 500);		// explicitly set size in pixels
		frame.setVisible(true);		// set to false to make invisible
	} // end Run()

	public void actionPerformed(ActionEvent evt) 
	{
        // This method is called when an action event occurs.
        // In this case, the only possible source of the event
        // is the button.  So, when this method is called, we know
        // that the button has been clicked.  Respond by showing
        // an informational dialog box.  The dialog box will
        // contain an "OK" button which the user must click to
        // dismiss the dialog box.

		String title = "YIKES!";  // Shown in title bar of dialog box.
        String message = "Ouch, don't click so hard next time!";
		JOptionPane.showMessageDialog(null, message, title,
                                        JOptionPane.INFORMATION_MESSAGE);
	} // end actionPerformed()
} // end class HelloSwing