If ScrollPane has wheel scrolling disabled with setWheelScrollingDisabled(false), but then has a MouseWheelListener added to it, it will still scroll in response to the wheel mouse. The following code demonstrates this:

 // test to make sure clients can install their own behavior on a ScrollPane

import java.awt.*;
import java.awt.event.*;

public class OverrideTest extends Frame {
    public static void main(String args[]) {
        OverrideTest frame = new OverrideTest();
        frame.show();
    }

    public OverrideTest() {
        super("OverrideTest");
        setSize(300, 300);
        Panel pnl = new Panel();
        pnl.setLayout(new GridLayout(10, 10));
        for (int i = 0; i < 100; i++) {
            pnl.add(new Label("Label " + i));
        }
        ScrollPane sp = new ScrollPane();
        sp.add(pnl);
        sp.setWheelScrollingEnabled(false);
        sp.addMouseWheelListener(new MWL());
        add(sp);
        addWindowListener(new WindowAdapter() {
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });
        pack();
    }

    class MWL implements MouseWheelListener {
        public void mouseWheelMoved(MouseWheelEvent e) {
            System.out.println("mouse wheel received. should not scroll");
        }
    }
}

Commenting out the addMouseWheelListener() line makes the problem disappear.

brent.christian@eng 2000-09-19