Name: gm110360 Date: 07/11/2002


FULL PRODUCT VERSION :
java version "1.4.0"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.0-b92)
Java HotSpot(TM) Client VM (build 1.4.0-b92, mixed mode)

FULL OPERATING SYSTEM VERSION : Windows NT Version 4.0


A DESCRIPTION OF THE PROBLEM :

Steps.

1. remove all elements in a JCombobox.
2. add new items to the JComboBox.
3. set selected index of combo box as zero.

Result.

in jdk1.3.1 item state change event will be fired always.
in jdk 1.4.0 itemStateChange even will be fired only if the
display string is different from the display String which
was selected before removing all items in the combobox



REGRESSION. Last worked in version 1.3.1

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :

1. Load a JComboBox with a list of string values. set
selected index as 0. itemStateChanged event will be
genereated.

2. Remove all items in combo box using combo.removeAllItems

3. Load the the combobox again with the same list of
strings used in step 1. set selected index as 0. This time
itemStateChanged will not be fired in jdk1.4.0 , but in
jdk1.3.1 it is fired.

EXPECTED VERSUS ACTUAL BEHAVIOR :

The itemSstateChanged event should be fired.

This bug can be reproduced always.

---------- BEGIN SOURCE ----------




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

/**
* author Abhilash K Bhaskaran
*
* Click on "reload" button multiple times in jdk1.3.1 and
* jdk1.4.0 to see the result.
*/
public class TEST extends JFrame{
private JButton reload ;
private JComboBox combo ;

public void init(){
combo = new JComboBox() ;
combo.addItemListener( new ItemListener(){
public void itemStateChanged( ItemEvent event ){
if (null != combo.getSelectedItem() &&
event.getStateChange() ==
ItemEvent.SELECTED){
System.out.println("S:"+
combo.getSelectedItem()) ;
}
}
} );
reload = new JButton("reload") ;
reload.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
loadCombo() ;
}
}) ;
JPanel panel = new JPanel(new BorderLayout()) ;
panel.add(combo,BorderLayout.NORTH) ;
panel.add(reload,BorderLayout.SOUTH) ;
getContentPane().add(panel) ;
}
public void loadCombo(){
combo.removeAllItems() ;
for (int iCount = 0 ; iCount <10 ; iCount++){
String strItem = "Item-"+iCount ;
combo.addItem(strItem) ;
}

try{
combo.setSelectedIndex(0) ;
}catch(Exception e){}
}
public static final void main(String args[]){
TEST app = new TEST() ;
app.init() ;
app.setSize(100,100) ;
app.setVisible(true) ;
app.loadCombo() ;
}
}
---------- END SOURCE ----------

Release Regression From : 1.3.0_03
The above release value was the last known release where this
bug was known to work. Since then there has been a regression.

(Review ID: 139926)
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