public class PaintPanel extends JPanel
1: // Fig. 11.32: PaintPanel.java
2: // Using class MouseMotionAdapter.
3: import java.awt.Point;
4: import java.awt.Graphics;
5: import java.awt.event.MouseEvent;
6: import java.awt.event.MouseMotionAdapter;
7: import javax.swing.JPanel;
8:
9: public class PaintPanel extends JPanel
10: {
11: private int pointCount = 0; // count number of points
12:
13: // array of 10000 java.awt.Point references
14: private Point points[] = new Point[ 10000 ];
15:
16: // set up GUI and register mouse event handler
17: public PaintPanel()
18: {
19: // handle frame mouse motion event
20: addMouseMotionListener(
21:
22: new MouseMotionAdapter() // anonymous inner class
23: {
24: // store drag coordinates and repaint
25: public void mouseDragged( MouseEvent event )
26: {
27: if ( pointCount < points.length )
28: {
29: points[ pointCount ] = event.getPoint(); // find point
30: pointCount++; // increment number of points in array
31: repaint(); // repaint JFrame
32: } // end if
33: } // end method mouseDragged
34: } // end anonymous inner class
35: ); // end call to addMouseMotionListener
36: } // end PaintPanel constructor
37:
38: // draw oval in a 4-by-4 bounding box at specified location on window
39: public void paintComponent( Graphics g )
40: {
41: super.paintComponent( g ); // clears drawing area
42:
43: // draw all points in array
44: for ( int i = 0; i < pointCount; i++ )
45: g.fillOval( points[ i ].x, points[ i ].y, 4, 4 );
46: } // end method paint
47: } // end class PaintPanel
48:
49:
50: /**************************************************************************
51: * (C) Copyright 1992-2005 by Deitel & Associates, Inc. and *
52: * Pearson Education, Inc. All Rights Reserved. *
53: * *
54: * DISCLAIMER: The authors and publisher of this book have used their *
55: * best efforts in preparing the book. These efforts include the *
56: * development, research, and testing of the theories and programs *
57: * to determine their effectiveness. The authors and publisher make *
58: * no warranty of any kind, expressed or implied, with regard to these *
59: * programs or to the documentation contained in these books. The authors *
60: * and publisher shall not be liable in any event for incidental or *
61: * consequential damages in connection with, or arising out of, the *
62: * furnishing, performance, or use of these programs. *
63: *************************************************************************/