public class ColorDemoApplet extends JApplet implements ActionListener
1:
2: import javax.swing.JApplet;
3: import javax.swing.JButton;
4: import javax.swing.JTextField;
5: import java.awt.Color;
6: import java.awt.Container;
7: import java.awt.FlowLayout;
8: import java.awt.Graphics;
9: import java.awt.event.ActionEvent;
10: import java.awt.event.ActionListener;
11:
12: public class ColorDemoApplet extends JApplet implements ActionListener
13: {
14: public static final int WIDTH = 400;
15: public static final int HEIGHT = 300;
16: public static final int NUMBER_OF_CHAR = 20;
17:
18: private JTextField colorName;
19:
20: public void init()
21: {
22: Container contentPane = getContentPane( );
23: contentPane.setBackground(Color.GRAY);
24: contentPane.setLayout(new FlowLayout( ));
25:
26: JButton showButton = new JButton("Show Color");
27: showButton.addActionListener(this);
28: contentPane.add(showButton);
29:
30: colorName = new JTextField(NUMBER_OF_CHAR);
31: contentPane.add(colorName);
32: }
33:
34: public void actionPerformed(ActionEvent e)
35: {
36: Container contentPane = getContentPane( );
37:
38: try
39: {
40: contentPane.setBackground(
41: getColor(colorName.getText()));
42: }
43: catch(UnknownColorException exception)
44: {
45: colorName.setText("Unknown Color");
46: contentPane.setBackground(Color.GRAY);
47: }
48: }
49:
50: public Color getColor(String name) throws UnknownColorException
51: {
52: if (name.equalsIgnoreCase("RED"))
53: return Color.RED;
54: else if (name.equalsIgnoreCase("WHITE"))
55: return Color.WHITE;
56: else if (name.equalsIgnoreCase("BLUE"))
57: return Color.BLUE;
58: else if (name.equalsIgnoreCase("GREEN"))
59: return Color.GREEN;
60: else
61: throw new UnknownColorException();
62: }
63: }