/**
 * A Simple stand-alone GUI program based on Swing.
 *  
 * This example uses a class that extends JFrame
 * instead of creating a JFrame object!
 * The main creates a window with a bunch of buttons 
 * and a textfield.
 * Uses a JPanel to hold the buttons (container component).
 *
 * Whenever the user does something with the mouse
 * (related to a button), the textfield changes to
 * display what is happening.
 *
 * This sample is based (in part) on code supplied in
 * an example found at java.sun.com (how to write a mouse listener
 * tutorial).
 * @author Dave Hollinger
 * @version 1.0
 */

import javax.swing.*;
import java.awt.*;       // needed for Container
import java.awt.event.*;  // needed for event types (listeners)


class MouseEvents extends JFrame {

  // The textfield must not be anonymouse, since we want to	
  // be able to modify it from event handlers

  JTextArea jt;

  // main just creates a new MouseEvent Object
  // (which is a special kind of JFrame).

  public static void main(String [] args) {
	MouseEvents me = new MouseEvents();
  }

  // Constructor sets up the window and gets things rolling.

  MouseEvents() {

	Container c = getContentPane();
	// set up layout manager
	c.setLayout(new BorderLayout(10,10));
	
	// add a button panel 
	c.add( createButtonPanel(), BorderLayout.NORTH );
	
	// add single text Area
	jt = new JTextArea(5,20);
	jt.setSize(100,20);
	jt.setFont(new Font("Arial",Font.BOLD,16));
	jt.setBackground(Color.WHITE);
	jt.setForeground(Color.BLUE);
	c.add(jt,BorderLayout.CENTER);

	// establish what happens when the window is closed
	// (without this the program would keep running!)
	setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	// set the size
	setSize(200,200);
	// turn it on
	setVisible(true);
  }


  JPanel createButtonPanel() {
	// create a JPanel with a bunch of buttons in it arranged in
	// a grid.
	JPanel jp = new JPanel();

	// establish the layout manager
	// 2 rows, 3 cols everything 5 pixels apart
	jp.setLayout( new GridLayout(2,3,5,5));

	// Create a mouse event listener object (code is below)
	// that will handle events
	MouseHandler mh = new MouseHandler();

	// add a bunch of buttons
	for (int i=0;i<6;i++) {
	  JButton j = new JButton(new Integer(i).toString());
	  // change the font
	  j.setFont(new Font("Courier",Font.BOLD,20));

	  // change the colors
	  j.setBackground(Color.WHITE);
	  j.setForeground(Color.BLACK);

	  // set up the listener for this button
	  j.addMouseListener(mh);

	  // add the button to the panel
	  jp.add(j);
	}
	return(jp);
  }

  // here is a class that will implement the MouseListener
  // interface. This allows us to capture mouse related events
  // and update the textfield.

  class MouseHandler implements MouseListener {

	// each of these methods updates the text area field
	// to describe what has happend and what button it
	// happened to.

	public void mousePressed(MouseEvent e) {
	  updateText(e,"Pressed");
	}

	public void mouseReleased(MouseEvent e) {
	  updateText(e,"Released");
	}

	public void mouseEntered(MouseEvent e) {
	  updateText(e,"Entered");
	}

	public void mouseExited(MouseEvent e) {
	  updateText(e,"Exited");
	}

	public void mouseClicked(MouseEvent e) {
	  updateText(e,"Clicked");
	}

	public void updateText(MouseEvent e, String what) {
	  // get the button associated with the event
	  JButton j = (JButton) e.getComponent();

	  // get the button text
	  String butname = j.getText();

	  // update the text area
	  jt.setText("Button " + butname + " " + what);
	}
  }
}