// Fig. 13.4: SelfContainedPanel.java
// A self-contained JPanel class that
// handles its own mouse events.
package com.deitel.jhtp4.ch13;

// Java core packages
import java.awt.*;
import java.awt.event.*;

// Java extension packages
import javax.swing.*;

public class SelfContainedPanel extends JPanel {
   private int x1, y1, x2, y2;

   // set up mouse event handling for SelfContainedPanel
   public SelfContainedPanel()
   {
      // set up mouse listener
      addMouseListener(

         // anonymous inner class for mouse pressed and 
         // released event handling
         new MouseAdapter() {

            // handle mouse press event
            public void mousePressed( MouseEvent event )
            {
               x1 = event.getX();
               y1 = event.getY();
            }

            // handle mouse release event
            public void mouseReleased( MouseEvent event )
            {
               x2 = event.getX();
               y2 = event.getY();
               repaint();
            }

         }  // end anonymous inner class

      ); // end call to addMouseListener

      // set up mouse motion listener
      addMouseMotionListener(

         // anonymous inner class to handle mouse drag events
         new MouseMotionAdapter() {
 
            // handle mouse drag event
            public void mouseDragged( MouseEvent event )
            {
               x2 = event.getX();
               y2 = event.getY();
               repaint();
            }

         }  // end anonymous inner class

      ); // end call to addMouseMotionListener

   }  // end constructor

   // return preferred width and height of SelfContainedPanel
   public Dimension getPreferredSize()
   {
      return new Dimension( 150, 100 );
   }

   // paint an oval at the specified coordinates
   public void paintComponent( Graphics g )
   {
      super.paintComponent( g );

      g.drawOval( Math.min( x1, x2 ), Math.min( y1, y2 ),
         Math.abs( x1 - x2 ), Math.abs( y1 - y2 ) );
   }

}  // end class SelfContainedPanel


/**************************************************************************
 * (C) Copyright 2002 by Deitel & Associates, Inc. and Prentice Hall.     *
 * All Rights Reserved.                                                   *
 *                                                                        *
 * DISCLAIMER: The authors and publisher of this book have used their     *
 * best efforts in preparing the book. These efforts include the          *
 * development, research, and testing of the theories and programs        *
 * to determine their effectiveness. The authors and publisher make       *
 * no warranty of any kind, expressed or implied, with regard to these    *
 * programs or to the documentation contained in these books. The authors *
 * and publisher shall not be liable in any event for incidental or       *
 * consequential damages in connection with, or arising out of, the       *
 * furnishing, performance, or use of these programs.                     *
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