Swing I - Java - page 956

theColor = c;
thePanel = p;
}

public void actionPerformed(ActionEvent e)
{
thePanel.setBackground(theColor);
}
} //End of ColorListener inner class

Replace

redChoice.addActionListener( new RedListener());

with

redChoice.addActionListener(
new ColorListener(Color.RED, redPanel));

Also make similar changes to the menu items whiteChoice and blueChoice , with
the obvious changes to colors and panels.
This is not really preferable to what we did in Display 17.16, but it is a good
exercise. The complete program done this way is on the accompanying CD in
the file named InnerListenersDemo2.java .

extra code
on CD

36. A JTextField object displays only a single line. A JTextArea object can display

more than one line of text.

37. The contents of the text field would change to "Hello Hello Hello " followed

by your name.

extra code
on CD

38. This program is on the CD that accompanies this text.

import javax.swing.JFrame;
import javax.swing.JTextArea;
import javax.swing.JPanel;
import javax.swing.JLabel;
import javax.swing.JButton;
import java.awt.GridLayout;
import java.awt.BorderLayout;
import java.awt.FlowLayout;
import java.awt.Color;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;

public class TextAreaDemo extends JFrame
implements ActionListener
{
public static final int WIDTH = 400;
public static final int HEIGHT = 200;
public static final int NUMBER_OF_LINES = 10;