Calculate the rectangle size displayed in JScrollPane

Question

Hi,
I am pasting a code below, What i want to get is the the rectangle of panel which will be displayed, so i can use g.setClip method to only paint that much portion of the JPanel
Please copy the code compile it and run it, so u will come to know my problem..
I want to dynamically setClip so the display is proper when the user scrolls.
Ashish
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class TestDisplaySize extends JFrame
     JScrollPane scrollPane ;
     public TestDisplaySize()
          super("layered pane");
          this.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
          MyPanel panel = new MyPanel();
          scrollPane = new JScrollPane(panel);
          Container contentPane = this.getContentPane();
          contentPane.add(scrollPane, BorderLayout.CENTER);
          setSize(new Dimension(800,600));
          this.setVisible(true);
     class MyPanel extends JPanel
          public MyPanel()
     setPreferredSize(new Dimension(2000,600) );     
     this.setBackground(Color.white);
     this.setOpaque(true);
     public void paintComponent(Graphics g)
super.paintComponent(g);
g.setClip(0,0, 750,550);
g.setColor(Color.blue);
int x = 0;
for(int i = 0; i < 60; i++)
     x +=60;
     g.drawLine(x, 0, x, 600);
     public static void main(String args[])
     new TestDisplaySize();
}

Answer 1

ash,
Use this:
super.paintComponent(g);
Rectangle r = scrollPane.getViewport().getViewRect();
g.setClip((int)r.getX(), (int)r.getY(), (int)r.getWidth(), (int)r.getHeight());
g.setColor(Color.blue);--A
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