Name: joT67522 Date: 09/09/97


When a lightweight component is added to ScrollPane
and at one point it does getParent() call, getParent()
java.awt.Panel[panel0,0,0,186x166,layout=java.awt.BorderLayout]
not a ScrollPane.
run the first program:
import java.awt.*;
import java.awt.event.*;
 
public class MyFrame extends Frame
{
        ScrollPane pane;
        class comp extends Component {
 
                public comp(){}
                public void paint(Graphics g) {
                        System.out.println(getParent());
                }
        }
 
 
        public MyFrame() {
                super();
                add(pane = new ScrollPane(ScrollPane.SCROLLBARS_AS_NEEDED));
                pane.add(new comp());
        }
 
        public static void main(String [] args) {
                MyFrame f = new MyFrame();
                f.setSize(200,200);
                f.setVisible(true);
        }
}

It will print:
java.awt.Panel[panel0,0,0,186x166,layout=java.awt.BorderLayout]
which is incorrect - it should print ScrollPane.


Run second program which adds a heavyweight component
to ScrollPane.
import java.awt.*;
import java.awt.event.*;
 
public class GoodFrame extends Frame
{
        ScrollPane pane;
        class comp extends Canvas{
 
                public comp(){}
                public void paint(Graphics g) {
                        System.out.println(getParent());
                }
        }
 
 
        public GoodFrame() {
                super();
                add(pane = new ScrollPane(ScrollPane.SCROLLBARS_AS_NEEDED));
                pane.add(new comp());
        }
 
        public static void main(String [] args) {
                GoodFrame f = new GoodFrame();
                f.setSize(200,200);
                f.setVisible(true);
        }
}

It will print correctly the parent of component:
java.awt.ScrollPane[scrollpane0,5,25,190x170,ScrollPosition=(0,0),Insets=(2,2,2,2),ScrollbarDisplayPolicy=as-needed]
company - AT&T , email - ###@###.###
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