Java Reference
In-Depth Information
Figure B.9. In this design, components that depend on the slider implement
ChangeListener
so that they can register for slider events.
SOLUTION 9.3
One solution is:
package com.oozinoz.applications;
import javax.swing.*;
import java.util.*;
import com.oozinoz.ballistics.Tpeak;
public class BallisticsLabel extends JLabel
implements Observer
{
public BallisticsLabel(Tpeak tPeak)
{
tPeak.addObserver(this);
}
public void update(Observable o, Object arg)
{
setText("" + ((Tpeak) o).getValue());
repaint();
}
}
Note that this solution places the
Tpeak
class in the
ballistics
package and
the
BallisticsLabel
class in the
applications
package.
