// Fig. 14.4: SelfContainedPanel.java // A self-contained JPanel class that handles its own mouse events. package com.deitel.jhtp5.ch14; import java.awt.*; import java.awt.event.*; 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( new MouseAdapter() { // anonymous inner class // 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( new MouseMotionAdapter() { // anonymous inner class // 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 SelfContainedPanel // 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 1992-2003 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. * *************************************************************************/