Name: ggC50526 Date: 08/29/97


Run the code, watch the output.
No matter what is clicked on the scrollbar, only one Adjustment
Event type is generated - TRACK. There is never UNIT_* event
nor BLOCK_* generated.

import java.awt.*;
import java.awt.event.*;
 
public class MyFrame extends Frame
{
        ScrollPane pane;
        class comp extends Component {
 
                public comp(){}
                public Dimension getPreferredSize() {
                        return new Dimension(400,400);
                }
        }
        class AdjustmentAdapter implements AdjustmentListener {
                public void adjustmentValueChanged(AdjustmentEvent e){}
        }
 
    AdjustmentAdapter adjustmentListener = new AdjustmentAdapter () {
            /**
             * Scrolls the column or row header depending on which scrollbar
             * in the scrollPane was clicked
             */
            public void adjustmentValueChanged(AdjustmentEvent e) {
            if (e.getAdjustmentType() == AdjustmentEvent.BLOCK_DECREMENT)
                System.out.println("BLOCK_DECREMENT");
            else if (e.getAdjustmentType() == AdjustmentEvent.BLOCK_INCREMENT)
                System.out.println("BLOCK_INCREMENT");
            else if (e.getAdjustmentType() == AdjustmentEvent.UNIT_DECREMENT)
                System.out.println("UNIT_DECREMENT");
            else if (e.getAdjustmentType() == AdjustmentEvent.UNIT_INCREMENT)
                System.out.println("UNIT_INCREMENT");
            else if (e.getAdjustmentType() == AdjustmentEvent.TRACK)
                System.out.println("TRACK");
            }
        };
 
 
 
 
        public MyFrame() {
                super();
                add(pane = new ScrollPane(ScrollPane.SCROLLBARS_AS_NEEDED));
                pane.add(new comp());
        pane.getHAdjustable().addAdjustmentListener(adjustmentListener);
        pane.getVAdjustable().addAdjustmentListener(adjustmentListener);
        }
 
        public static void main(String [] args) {
                MyFrame f = new MyFrame();
                f.setSize(200,200);
                f.setVisible(true);
        }
}

company - AT&T , email - ###@###.###
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