Name: vi73552 Date: 03/23/99


This bug occurs on Swing 1.1, JDK 1.1.7, Win NT. Haven't had a chance to test it on other platforms and JDK versions.

JSplitPane does not consider the size of its divider when calculating its maximum location before the divider is moved for the first time.

After compiling and executing the following code:

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class main extends JFrame
{
  public static void main(String[] args)
  {
    main f = new main();
    MainPanel m = new MainPanel();
    f.setContentPane(m);
    f.setSize(500, 500);
    f.show();
  }
}

class MainPanel extends JPanel
{
  public MainPanel()
  {
    JLabel l1 = new JLabel("Label 1");
    l1.setMinimumSize(new Dimension(0,0));
    JLabel l2 = new JLabel("Label 2");
    l2.setMinimumSize(new Dimension(0,0));
    JLabel l3 = new JLabel("Label 3");
    l3.setMinimumSize(new Dimension(0,0));
  
    setLayout(new BorderLayout());
    JSplitPane _horizontalSplit = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT, l1, l2);
    _horizontalSplit.setDividerSize(5);
    JSplitPane _verticalSplit = new JSplitPane(JSplitPane.VERTICAL_SPLIT, _horizontalSplit, l3);
    _verticalSplit.setDividerSize(5);
    add(BorderLayout.CENTER, _verticalSplit);
    JButton b = new JButton("Press here");
    b.addActionListener(new bList(_verticalSplit));
    add(BorderLayout.NORTH, b);
  }
}

class bList implements ActionListener
{
  JSplitPane _v;
  
  bList(JSplitPane v)
  {
    _v = v;
  }
  
  public void actionPerformed(ActionEvent e)
  {
    System.out.println(_v.getMaximumDividerLocation());
  }
}

Do the following:

1. Press the button
2. Move the _verticalSplit divider (that's the horizontal one)
3. Press the button again

Notice that the values are different, but they should be the same.

Interestingly though, the difference between these values is 7... which is 5 + 1 + 1 ---> divider size + top border thickness + bottom border thickness.

Somehow the divider is not being subtracted at first, but after it is moved JSplitPane seems to realize it has a certain thickness...

Try setting the divider size to 20 and you will see a difference of 22.....results are consistently off by: divider thickness + 2
(Review ID: 55947)
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