JComboBox event problem

Hi ,
I have JComboBox in my application. I added action listener for this. When I set the values programmatically I don't want the code in the actionperformed to be executed. I can do it indirectly by using boolean flag for this, but I want to know is there any other (neat) way we can achieve this.
Thanks

You can always check to see if there is a selected index...
myComboBox.addActionListener
     new ActionListener()
          public void actionPerformed(ActionEvent e)
               if (((JComboBox)e.getSource()).getSelectedIndex() != -1)
                    //perform your operations here.
);Another way to do it would be to write your own custom action listener and consume() any event that you don't want.
Hope that helps.

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InputField fire event problem in webDynpro

I have one validation or Fire Event problem with respect to Inputfield in web Dynpro.
I have one Input filed and created the context varible for that, then i mapped the context varible to the InputField, and i changed the context varible type as date.So , when i run the view , it will show the calender near to the text box to select the perticular date. On select of the perticular date. It will populate selected date in to the inputField.
On selection of the perticular date. Based on the date i want to generate the next 12 months date at runtime in different text boxes. But the only event available for the InputField is only "onEnter". This is not useful in my case, bcz on selection of the Date , the user may not use the Enter key. so , how can use the other events like onSelection or onChange events in the InputFields to reach my needs.
Any one give me the idea to solve this problem.
Vijay

Hello Vishal,
You may also refer the sample code in the below link
<a href="http://sdn.sap.comhttp://www.sdn.sap.comhttp://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/docs/library/uuid/0c0dcacd-0401-0010-b4bd-a05a0b4d68c8">http://sdn.sap.comhttp://www.sdn.sap.comhttp://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/docs/library/uuid/0c0dcacd-0401-0010-b4bd-a05a0b4d68c8</a>
Regards,
Sudeep.

More event problems

Hello again, I have yet another event problem. When I try to use this code I get an error saying Abstract class actionPerformed is not implemented in non- abstract class TableWindow. I'm not quit sure how I'm supposed to implement it.

Here is what I believe to be the relevant code. addWindowListener works but addFocusListener returns the error.
// Table window
import java.awt.*;
import java.awt.event.*;
import java.sql.*;
import javax.swing.*;
import javax.swing.event.*;
public class TableWindow extends Frame implements ActionListener
public TableWindow ()
Create Window
super ("Test Window");
setBackground (SystemColor.control);
setLocation (0, 0);
setLayout (new GridLayout (5, 5));
addWindowListener (new WindowAdapter ()
public void windowClosing (WindowEvent e)
try
if (Connected == true)
// Close the Statement
stmt.close ();
// Close the connection
con.close ();
catch (SQLException sqle)
dispose ();
System.exit (0);
tPane = new JTabbedPane ();
tPane.addChangeListener (new ChangeListener ()
public void stateChanged (ChangeEvent c)
//Status.setText ("Clicked");
tablePane = new JPanel ();
recordPane = new JPanel ();
recordPane.addFocusListener(new FocusListener()
public void focusGained(FocusEvent e)
Status.setText ("Clicked");
queryPane = new JPanel ();
TName1 = new TextField (25);
TName2 = new TextField (25);
TName3 = new TextField (25);
idField = new TextField (10);
idField2 = new TextField (10);
TitleField = new TextField (25);
TitleField2 = new TextField (25);
result = new TextArea ("Under Construction", 5, 30);
NewT = new Button ("New Table");
NewR = new Button ("New Record");
NewQ = new Button ("New Query");
NewT.addActionListener (this);
NewR.addActionListener (this);
NewQ.addActionListener (this);
TNameLabel1 = new Label ("Enter name of table here");
TNameLabel2 = new Label ("Enter name of table here");
TNameLabel3 = new Label ("Enter name of table here");
idLabel = new Label ("Enter movie ID here");
TitleLabel = new Label ("Enter title of Movie here");
TitleLabel2 = new Label ("Enter title of Movie here");
tablePane.add (TNameLabel1);
tablePane.add (TName1);
tablePane.add (NewT);
recordPane.add (TNameLabel2);
recordPane.add (TName2);
recordPane.add (idLabel);
recordPane.add (idField);
recordPane.add (TitleLabel);
recordPane.add (TitleField);
recordPane.add (NewR);
//recordPane.add (tableChoice);
queryPane.add (TNameLabel3);
queryPane.add (TName3);
queryPane.add (TitleLabel2);
queryPane.add (TitleField2);
queryPane.add (NewQ);
queryPane.add (result);
Status = new Label ("");
// make the window and add components to it
tPane.addTab ("Table", tablePane);
tPane.addTab ("Record", recordPane);
tPane.addTab ("Query", queryPane);
add (tPane, BorderLayout.CENTER);
add (Status, BorderLayout.SOUTH);
pack ();
setVisible (true);
public static void main (String args [])
ConnectToDatabase ("vdds");
TableWindow tw = new TableWindow ();
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Event problem with JComboBox

Hi, javamen.
I ve gotten a little problem when working with Itemlistener interface. My combo has 4 options, in which the first one always appears when the applet starts up. Whenever the user DOESNT change it and submit the applet form, throught a button click, the applet gets a NullPointerException. But, if the user changes the option, i always get it, throught my interface' methods(ItemStateChanged). Of course, i know its because there was no combobox event, just a button event (click). So, how can i deal with this situation, since i need to get the combobox option content.
Regards, Euclides.

But, this is the question! I dont know how to initialize the combobox' first option. Help me, please! I am using the addItem method as follow:
MakeJCombo ( JComboBox ComboObj) {
ComboObj.addItem ("option1");
ComboObj.addItem ("option2");
ComboObj.addItem ("option3");
then:
public void itemStateChange(ItemEvent ie) ...
Object origem = ie.getSource()...
if (origem == ComboObj) ...

Multiple JComboBox Event Handling Problem

Hi, guys
I am a newbie in Java. I need to create three JComboBox, say date, month and year and a JButton "submit". After I select the entries from the three JComboBox, I click the "search" button to display something in terms of the information I selected, but I have no idea how to write the actionPerformed( ActionEvent evt) to deal with the problem. Can anyone give me some hint?
Any help would be appreciated.

If you are asking how to write a basic event handler for when your button is pressed, RTM.
http://java.sun.com/docs/books/tutorial/uiswing/events/index.html

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I have a complex UI with which I am having action event issues. Basically, the panel displays info about an object, which can be selected from within the panel through a button/popup window mechanism. A JComboBox (#1) selection determines the contents of another JComboBox (#2) on the same panel. Currently an ActionEvent fires when the user makes a selection using #1 that updates #2. This fuctions correctly with repeated testing so long as a new object is not selected.
When a new object is selected from within this panel this ActionEvent no longer fires. JComboBox #1 will be updated correctly and #2 will reflect the initial selection in #1, but user selections in #1 will not fire the ActionEvent and thus #2 is never updated.
Any help is appreciated. I feel like I'm missing something basic here, but I've stared at it for long enough...

By the way, the workaround is to use the ItemListener as the ItemStateChanged Event is fired reliably.

JCombobox selection problem

Hello,
I have some problem implementing events associated with JComboBox. My requirement is "the event should get fired only when an item is selected in the combobox". It may occur thet using arrow keys I can traverse all elements in the combobox and on item change the event should not get fired. I tried with itemstatechanged, actionperformed but no result.
Any help will be appreciated.
regards,
Ranjan

A simple working example:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.text.*;
public class ComboBoxAction extends JFrame implements ActionListener
     private JComboBox comboBox;
     public ComboBoxAction()
          comboBox = new JComboBox();
          comboBox.addActionListener( this );
          comboBox.addItem( "Item 1" );
          comboBox.addItem( "Item 2" );
          comboBox.addItem( "Item 3" );
          comboBox.addItem( "Item 4" );
          // This prevents action events from being fired when the
          // up/down arrow keys are used on the dropdown menu
          comboBox.putClientProperty("JComboBox.isTableCellEditor", Boolean.TRUE);
          getContentPane().add( comboBox );
     public void actionPerformed(ActionEvent e)
          System.out.println( comboBox.getSelectedItem() );
          // make sure popup is closed when 'isTableCellEditor' is used
          comboBox.hidePopup();
     public static void main(String[] args)
          JFrame frame = new ComboBoxAction();
          frame.setDefaultCloseOperation( EXIT_ON_CLOSE );
          frame.pack();
          frame.setVisible( true );
}

JComboBox listener problem

Hi all,
I have following problem, i use combobox and i need to write listener for selecting item.
But both ActionListener and ItemListener are unusable for me, because i dont know how to differ between selecting item when combobox is poped up.
I dont want to react on going thru items in popup, but only to FINAL select of button.
Please Help.
Mathew, HSIGP

     This works on non editable combo boxes
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.text.*;
public class ComboBoxAction extends JFrame implements ActionListener
     JComboBox comboBox;
     public ComboBoxAction()
          comboBox = new JComboBox();
          comboBox.addActionListener( this );
          comboBox.addItem( "Item 1" );
          comboBox.addItem( "Item 2" );
          comboBox.addItem( "Item 3" );
          comboBox.addItem( "Item 4" );
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          // up/down arrow keys are used on the dropdown menu
          comboBox.putClientProperty("JComboBox.isTableCellEditor", Boolean.TRUE);
          getContentPane().add( comboBox );
     public void actionPerformed(ActionEvent e)
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          comboBox.hidePopup();
     public static void main(String[] args)
          final ComboBoxAction frame = new ComboBoxAction();
          frame.setDefaultCloseOperation( EXIT_ON_CLOSE );
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}

JComboBox Render Problem........

Hi I have a problem in JCombox renderer in my application Problem is i have Three comboBox columns in my table wing same Renderer and Editor. second and third combo column's aree working fine But in first combo-column if i add a new row clicking add button and if change a value in top- most comboBox i will reflect in all ComboBox's below, this is not happening in othe two Combo-column. i'am not at all gettin why this happens where i am using same renderer for all combo-columns how to stop this, When a new row is add ComboBox first item as Selected,
Can any one please tell me how to solve this,
since i cannot past entair application i am pasting example with similar suituation using same renderer.
Thank's in Advance
CODE:-
import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.DefaultCellEditor;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.table.DefaultTableModel;
import javax.swing.table.TableCellRenderer;
import javax.swing.table.TableColumn;
* @author 501376972
public class MainTable extends JFrame{
DefaultTableModel model = null;
JTable table = null;
JScrollPane scrollpane = null;
JButton btCancel = null;
JButton btADD = null;
JPanel panelButton = null;
public Object[][] data = null;
String column[] = {" ","A","B","C","D","E","F"};
String oprator[] = {" ","=","/","*","-","+"};
String number[] = {" ","1","2","3","4","5","6"};
/** Creates a new instance of MainTable */
public MainTable() {
model = new DefaultTableModel();
model.addColumn("Column");
model.addColumn("Operator");
model.addColumn("Value");
model.addColumn("Number");
table = new JTable();
table.setModel(model);
data = new Object[][]{
{column, oprator, null, number}
model.addRow(data);
TableColumn colCol = table.getColumnModel().getColumn(0);
colCol.setCellRenderer(new ComboBoxCellRenderer(column));
colCol.setCellEditor(new ComboBoxCellEditor(column));
TableColumn colOpr = table.getColumnModel().getColumn(1);
colOpr.setCellRenderer(new ComboBoxCellRenderer(oprator));
colOpr.setCellEditor(new ComboBoxCellEditor(oprator));
TableColumn colLog = table.getColumnModel().getColumn(3);
colLog.setCellRenderer(new ComboBoxCellRenderer(number));
colLog.setCellEditor(new ComboBoxCellEditor(number));
scrollpane = new JScrollPane(table);
getContentPane().setLayout(new BorderLayout());
getContentPane().add(scrollpane,BorderLayout.CENTER);
panelButton = new JPanel();
btADD = new JButton("ADD");
btCancel = new JButton("Cancel");
panelButton.add(btADD);
panelButton.add(btCancel);
getContentPane().add(panelButton,BorderLayout.SOUTH);
btCancel.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e) {
dispose();
btADD.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e) {
model.addRow(data);
getContentPane().add(scrollpane);
setSize(500,500);
class ComboBoxCellRenderer extends JComboBox implements TableCellRenderer {
public ComboBoxCellRenderer(String[] items) {
super(items);
public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column) {
if (isSelected) {
//DO NOTHIING
} else {
//DO NOTHIING
// Select the current value
if(value == null)
setSelectedIndex(0);
else
setSelectedItem(value);
return this;
public class ComboBoxCellEditor extends DefaultCellEditor {
public ComboBoxCellEditor(String[] items) {
super(new JComboBox(items));
* @param args the command line arguments
public static void main(String[] args) {
MainTable mt = new MainTable();
mt.setVisible(true);
}

Don't forget to use the [url http://forum.java.sun.com/help.jspa?sec=formatting]Code Formatting Tags so the posted code retains its original formatting.
Don't know why the code works the way it does, but the code is wrong. The correct way to add a row is like this:
//model.addRow(data);
String[] rowData = { " ", " ", " ", " "};
model.addRow(rowData);

JComboBox MouseListener Problem

Hi!
I have problem in getting mouseEntered event from a JComboBox. I have registered a MouseListener with it but it doesn't fire any mouseEvent. Anyone has any idea how to get the mouseEntered Event fired from a JComboBox??
Thanks!!

Even I, have a similar problem. My obejective is to display the tooltip, When I move the mouse over every individual item in the combo box. The combo basically has a JList. So, I overrided the getListCellRenderer(...) method. It is not displaying the toolTip when the combo initially has no selectedItem. If there is a selected item, the first time itslef, it displays the toolTip. If theres no selectedItem, it displays the toolTip when I move the mouse out of the combo(when the combo is expanded). Tried all possible combinations... but doesnt work. Have set the toolTip with setToolTipText() method... and when I print the toolTip with getToolTipText() method. It prints correctly, but isnt getting displayed.. :-(

JComboBox event ItemChanged is called repeatedly

Hi all,
I've got an JApplet with 2 JComboBoxes. The first both of them are added to ItemListener.
When a entry of the first ComboBox is selected I delete
the contents of the second one and add other contents.
(I have to do so)
The problem :
The itemStateChanged event occurs of Combo2 occurs
after itemStateChanged of Combo1 and vice versa multiple times.
How can I avoid this. When I select an item from combo1
only this event should occure. When I select an item from combo2 only this event should occure.
public void itemStateChanged(ItemEvent ie) {
      String sName = (String)ie.getItem();
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            if(sName.compareTo("BML-V2") == 0) {
               ((CQdbl_Beanstandung)m_appletParent).setBmlv2();
            } else if(sName.compareTo("BML-V1/WE") == 0) {
               ((CQdbl_Beanstandung)m_appletParent).setBmlv1we();
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make a variable itemStateThatOughtToBe
in your ItemListenrer first ask if the current itemstate is istemStateThatOughtToBe. if return else execute your normal code.
If you don't want the itemlistener to become active with this particualr change first set ItemStateTahtOughttoBe and then change the item

JComboBox Event help

sir
i have three JComboBoxes .
firstcombobox will be loaded on start up .
basing on the First combobox item selected the second combo box is filled up.
basing on the second the third one will be filled up.
based on the third combobox the text feild beside it should be locked or unlocked
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in the following link there is a code example it will help u and u have to make combobox model to all stuff
http://forum.java.sun.com/thread.jspa?forumID=57&threadID=688505

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Hi,
I use an ActiveX component with Java and i've got a problem with events.
Java classes were generated with Bridge2Java (IBM).
In order to manage events I added a listener in my application :
javaMyActiveX = new MyActiveX();
javaMyActiveX.add_DMyActiveXEventsListener(new _DMyActiveXEventsAdapter());
I also added a constructor in the _DMyActiveXEventsAdapter class and I fill the body of methods.
The ActiveX generates two types of events :
- The ones are directly generated by methods.
- The others are generated by a thread.
With MS Products (VB, Visual C++, Visual J++), I catch all events.
With java (jdk 1.4), I catch only events generated by methods.
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I'm not 100% sure, but the last time I used that bridge, it only worked if you ran your Java app within a Microsoft VM.

Help needed with Image Events problem

Hi there I'm writing what I thought was a simple script to convert a folder full of images from jpg to tiff. But the script fails when trying to convert the first image in the folder. Instead of converting the image, Preview opens with the image shown and I get this error message: error "The variable ImageRef is not defined." number -2753 from "ImageRef".
I have seen some posts about other people having the same problem, but I haven't seen any solutions.
Here's the script.
on run
tell application "Finder"
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set Photographs to (get entire contents of PicturesFolder) as alias list
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tell application "Image Events"
launch
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end if
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end tell
tell application "Finder"
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end repeat
end tell
end run
Thanks in advance for any help.
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Hello
You may try something like the modified code below.
Noticiable changes :
#1 - Removed the parentheses. Your original code won't yield alias list but a list of finder objects, which is the reason why Preview opens the image. (The statment 'open finderObject' behaves the same as double clicking it in Finder)
#2 - Only delete the original jpeg files which are converted to tiff.
#3 - Build new path for converted image.
#4 - Save in new path. (When saving image in a format other than its original format, always save the image to a new file and do not attempt to overwrite the source file.)
cf.
http://www.macosxautomation.com/applescript/imageevents/08.html
on run
tell application "Finder"
set PicturesFolder to (path to home folder as string) & "Pictures:SenseCam:" as alias
set Photographs to get entire contents of PicturesFolder as alias list -- #1
end tell
set DonePhotos to {} -- #2
tell application "Image Events"
launch
repeat with Photo in Photographs
set Photo to Photo's contents
set oldPath to Photo as string
if oldPath ends with ".jpg" then
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set ImageRef to open Photo
save ImageRef as TIFF in newPath -- #4
close ImageRef
set end of DonePhotos to Photo -- #2
end if
end repeat
end tell
tell application "Finder"
delete DonePhotos -- #2
end tell
end run
Hope this may help,
H

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JComboBox event problem

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