Graphical User Interfaces - Building Java Programs: A Back to Basics Approach - page 873

22 g = image.getGraphics();
23 g.setColor(Color.BLACK);
24
25 // encloses the image in a label inside a panel
26 JLabel label = new JLabel();
27 label.setIcon( new ImageIcon(image));
28 panel = new JPanel( new FlowLayout());
29 panel.setBackground(Color.WHITE);
30 panel.setPreferredSize( new Dimension(width, height));
31 panel.add(label);
32
33 // the status bar that shows the mouse position
34 statusBar = new JLabel(" ");
35
36 // attaches listener to observe mouse movement
37 panel.addMouseListener( this );
38 panel.addMouseMotionListener( this );
39
40 // sets up the JFrame
41 frame = new JFrame("Drawing Panel");
42 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
43 frame.setResizable( false );
44 frame.setLayout( new BorderLayout());
45 frame.add(panel, BorderLayout.CENTER);
46 frame.add(statusBar, BorderLayout.SOUTH);
47 frame.pack();
48 frame.setVisible( true );
49
50 // starts a repaint timer to refresh the screen
51 Timer timer = new Timer(250, this );
52 timer.start();
53 }
54
55 // obtains the Graphics object to draw on the panel
56 public Graphics getGraphics() {
57 return g;
58 }
59
60 // sets the background color of the drawing panel
61 public void setBackground(Color c) {
62 panel.setBackground(c);
63 }
64
65 // shows or hides the drawing panel on the screen