Name: rm29839 Date: 01/06/98


I created an editable JEditorPane.
I typed some text and then deleted the text.
The caret started in the middle of the line.
Then when I started typing it move to the left
margin.
As I typed the caret appeared to move further and
further than the acutal text that appeared.
As I deleted the text the caret appeared to move
back closer to the text that appeared.

When I deleted all of the text the caret appeared
back to the middle. Then if I typed again I
recieved an exception.

-------- Here is the code

import java.awt.*;
import java.awt.event.*;
import com.sun.java.swing.*;

public class WeoEditor extends JEditorPane
{
public WeoEditor() {
setEditable(true);
}

public static void main(String args[])
{
JFrame frame = new JFrame();
WeoEditor weoeditor = new WeoEditor();
Container c = frame.getContentPane();
c.add(weoeditor, BorderLayout.CENTER);
frame.addWindowListener(new WindowAdapter()
{
public void windowClosing(WindowEvent e)
{
System.exit(0);
}
});
frame.setSize(300,100);
frame.setVisible(true);
}
}

--------- Here is the Exception

Exception occurred during event dispatching:
java.lang.NullPointerException:
        at com.sun.java.swing.text.DefaultStyledDocument$ElementBuffer.open(Defa
ultStyledDocument.java:1238)
        at com.sun.java.swing.text.DefaultStyledDocument$ElementBuffer.insertUpd
ate(DefaultStyledDocument.java:798)
        at com.sun.java.swing.text.DefaultStyledDocument$ElementBuffer.insert(De
faultStyledDocument.java:750)
        at com.sun.java.swing.text.DefaultStyledDocument.insertUpdate(DefaultSty
ledDocument.java:392)
        at com.sun.java.swing.text.AbstractDocument.insertString(AbstractDocumen

t.java:243)
        at com.sun.java.swing.JTextPane.replaceSelection(JTextPane.java:157)
        at com.sun.java.swing.text.DefaultEditorKit$DefaultKeyTypedAction.action
Performed(DefaultEditorKit.java:325)
        at com.sun.java.swing.text.DefaultTextController.keyTyped(DefaultTextCon
troller.java:445)
        at java.awt.Component.processKeyEvent(Component.java:2455)
        at com.sun.java.swing.JComponent.processKeyEvent(JComponent.java:1091)
        at java.awt.Component.processEvent(Component.java:2347)
        at java.awt.Container.processEvent(Container.java:889)
        at java.awt.Component.dispatchEventImpl(Component.java:1909)
        at java.awt.Container.dispatchEventImpl(Container.java:934)
        at java.awt.Component.dispatchEvent(Component.java:1824)
        at java.awt.LightweightDispatcher.processKeyEvent(Container.java:1408)
        at java.awt.LightweightDispatcher.dispatchEvent(Container.java:1392)
        at java.awt.Container.dispatchEventImpl(Container.java:921)
        at java.awt.Window.dispatchEventImpl(Window.java:517)
        at java.awt.Component.dispatchEvent(Component.java:1824)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:160)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:45)
(Review ID: 22442)
======================================================================
Another bug related to the cursor position:
import java.awt.*;
import java.awt.event.*;
import java.awt.swing.*;

public class SimpleEvents extends JFrame {
   static final int WIDTH = 350;
   static final int HEIGHT = 180;
   JTextField textField;
   JTextArea textList;
   JScrollPane pane;

   public SimpleEvents(String lab) {
      super(lab);
      setLayout(new FlowLayout());
      setBackground(Color.lightGray);

      JPanel textPanel = new JPanel();
      textPanel.setBorder(BorderFactory.createEtchedBorder());
      textPanel.setLayout(new BorderLayout());
      JLabel textTitle = new JLabel("Type and hit");
      textPanel.add(textTitle, BorderLayout.NORTH);

      textField = new JTextField(10);

//What ever i am typing in this textfield my
//my cursor is not correctly pointing after i
//pressed a space bar in this field. It is very
//problematic when i want to delete any character
//after i type.

      textPanel.add(textField, BorderLayout.SOUTH);
      textPanel.add(Box.createVerticalStrut(6));

      JPanel listPanel = new JPanel();
      listPanel.setBorder(BorderFactory.createEtchedBorder());
      listPanel.setLayout(new BoxLayout(listPanel, BoxLayout.Y_AXIS));
      JLabel title = new JLabel("Text List");
      listPanel.add(title);
      listPanel.add(Box.createVerticalStrut(10));
      textList = new JTextArea("", 6, 10);
      textList.setEditable(false);
      pane = new JScrollPane();
      pane.getViewport().add(textList);

//Scroll bars are not comming for the textarea
//even though there are 20 lines in the text area

      listPanel.add(pane, BorderLayout.CENTER);
      listPanel.add(textList);
      listPanel.add(Box.createVerticalStrut(6));

      textField.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent e) {
            System.out.println(textField.getText());

// Here append is not working properly it is
// appending only first character from textField

            textList.append(textField.getText() + "\n");
            textList.append("\n");
            pane.validate();
            textField.setText("");
         }
         });
      Container c = getContentPane();
      c.setLayout(new FlowLayout());
      c.add(textPanel);
      c.add(Box.createHorizontalStrut(30));
      c.add(listPanel);
   }

   public static void main(String args[]) {
      SimpleEvents frame = new SimpleEvents("Simple Events Example");
      frame.addWindowListener(new WindowAdapter() {
            public void windowClosing(WindowEvent e) {
               System.exit(0);
            }
      });
      frame.setSize(WIDTH, HEIGHT);
      frame.setVisible(true);
   }
}