Handling Key Event

How to handle key events in the Console?
Plz give sample code for it.
Thanks in advance.

Don't have any experience with it personally, but I think curses does this type of thing http://sourceforge.net/projects/javacurses/

Similar Messages

How to handle key events in iphone

I want to be able to detect physical keyboard (e.g. bluetooth) events in an iOS app.
In Mac, there is a class NSEvent which handles both keyboard and mouse events, and in ios (iphone/ipad) the counterpart of NSEvent is UIEvent which handles only touch events. I know ios API does not provide this functionality, but how can i handle key events in iphone???

in my application header part of the page is common of all page. header.jsff contains comandmenuItem named "proceduralhelp". if I click proceduralhelp a pop up opens .
in my login page when first time I open popup and press escape popup is not closing.
rest of the cases after login escpe will cose the popup.
only on the loginpage that to for the first time it is not closing when pressing up on escape key. (then we click on close button. and once again open the popup in loginpage now if we press escape it works).
Thanks,
Raghavendra.

How to handle key events in popup component

Is there any possibility to handle keyboard events after a popup is opened
requirement : I want to close popup when I press escape key (by default this functionality is present but in some scenarios this is not working ) so explicitly i want to handle key events for popup.
Thanks,
Raghavendra.

in my application header part of the page is common of all page. header.jsff contains comandmenuItem named "proceduralhelp". if I click proceduralhelp a pop up opens .
in my login page when first time I open popup and press escape popup is not closing.
rest of the cases after login escpe will cose the popup.
only on the loginpage that to for the first time it is not closing when pressing up on escape key. (then we click on close button. and once again open the popup in loginpage now if we press escape it works).
Thanks,
Raghavendra.

Key event handler

What is the best approach to handling key events (listening for keys being pressed)?
Are there any widgets out there for this purpose? Just do it in JavaScript?
Thanks

The best 'approach' for key events in Captivate e-learning courses is to avoid them as much as possible. They are a can of worms because every browser is different in terms of which keystrokes it will allow you to use. So you may find that you can use certain keystrokes in one browser but only some of them will work in another.
Widgets are not the answer because they are ActionScript and AS calls are close to the bottom of the pile. JavaScript will also only get you so far because even that happens AFTER the browser gets first pick.

How to handle Shift+Tab key event

HI,
This is Ramesh.I have added KeyListener to JTable. I am handling key events through key codes. But I am
unable to handling multiple key strokes like Shift+Tab
Can any one please give me suggestion how can I do it
Thanks & Regards
Ramesh K

i dont know about Key BindingsWhich is why you where given a link to the tutorial in the first response.
can you please give me suggestion.You've been given the suggestion 3 times. You can decide to learn to write code the way other Swing components are written. Or, you can do it the old way. The choice is up to you.

How to block JTree key event listeners

I have a JToolbar I am managing keyboards events for (e.g. PageUp, PageDown, right, left, up, down). I also have a JTree in another panel. I have to use 'Alt + PageUp' instead of PageUp because, if I use 'PageUp' (without also using the Alt key), and, the JTree gets the focus, then the JTree will respond to 'PageUp' instead of my JToolbar.
I have my key actions in a 'getKeystrokeActions()' method which I pass the JToolbar into so I tried passing the JTree to the same method. This doesn't quite do what I want as both components now respond to a 'PageUp' key event.
There must be some way to tell the JTree not to handle key events but I can't seem to find it. Any help much appreciated.

Remove the key listeners?
JTree tree = new JTree();
for(KeyListener listener : tree.getKeyListeners()) {
tree.removeKeyListener(listener);
}Another option would be to just do
tree.setFocasable(false);

Sleutel Bind, fancy key events handler for standalone window managers

I began using Openbox in my laptop a while ago, and I was amazed by the speed, customization and simplicity it provides. After I started customizing my desktop I noticed that some of the special keys (TouchpadToggle, Volume, PrintScreen, etc) didn't worked at all. There are some applications for the Volume keys to work, but not for keys like touchpad-toggle and print-screen. Of course, there's a workaround for each case using simple scripts, but I wanted something a little more fancy, so I made:
Sleutel Bind
It's made in C and provides key events handling for:
XF86TouchpadToggle
Print (prtsc key)
It makes use of libnotify to display states ( touchpad enabled/disabled, screenshot taken, etc) and imlib2 (a very popular library, probably already installed in your system) to grab the screenshots. Almost all other keys are covered already by another application, but if needed, more key events will be added in the future.
Feel free to post your thoughts about Sleutel Bind, it's my first contribution to the community.
How to use
Once installed just run the command as a normal user.
If using openbox, place the following command in the "~/.config/openbox/autostart" file:
sleutelb &
Links
AUR
github
Last edited by DanielRS (2013-03-01 21:58:35)

mgmillani wrote:
I believe it must have been a bug and it was fixed, since print screen now works as expected. I'm using xmonad version 0.11-9, with ghc version 7.8.3.
davama wrote:
Note: for my print key to be recognized by xev i had to hold the ctrl key. that way it was not registered by xmonad. Also for xev command i use
xev | grep -A2 --line-buffered '^KeyRelease' | sed -n '/keycode /s/^.*keycode $[0-9]*$.* (.*, $.*$).*$/\1 \2/p'
Nice, that seems to be useful. Thanks!
@LQYMGT
Do you still have issues with the latest version? Otherwise I will mark this thread as solved.
well, still do not work... But I do not want to try it any more...So you can mark.

Handling Enter key event in JTable

Hi...
This is particularly for the user "VIRAVAN"...
I have followed your method ,and got results too.. but the
processKeyBinding(.. method is called 4 times,same problem addressed by you before, but I didn't understood it...
Please help me...
Here is my code...
protected boolean processKeyBinding(KeyStroke ks, KeyEvent e,int condition, boolean pressed)
System.out.println("Wait");
if (ks == KeyStroke.getKeyStroke(KeyEvent.VK_ENTER,0))
int selRow = getSelectedRow();
int rowCount = getRowCount();
int selCol = getSelectedColumn();
String val =(String)getValueAt(selRow,selCol);
boolean b= getCellEditor(selRow,selCol).stopCellEditing();
System.out.println(b);
System.out.println(rowCount-1 + " "+ selRow + " " + getSelectedColumn());
if((!val.equals("")) && selRow==rowCount-1)
System.out.println(rowCount-1 + " "+ getSelectedRow()+ " " + getSelectedColumn());
blank1 = new String[columns];
for(int p=0;p<columns;p++)
blank1[p]="";
Diary.this.datarows.addElement(blank1);
// dataModel.fireTableStructureChanged();
//dataModel.fireTableDataChanged();
Diary.this.dataModel.fireTableChanged(null);
else if(ks ==KeyStroke.getKeyStroke(KeyEvent.VK_1,0))
System.out.println("One One One One ");
return super.processKeyBinding(ks,e,condition,pressed);

It's been a while since I looked at the code, but essentially there are three key event types:
1) key pressed,
2) key typed,
3) key released.
So I would expect the processKeyBind to see all three of them. However, ks==KeyStroke.getKeyStroke(KeyEvent.VK_ENTER,0) is true only when a key typed event is detected (the other types can be ignored by passing it up the food chain where they will eventually be consumed). Now...., if I understand you correctly, you want to terminate edit on the present of Enter key, right? Here is how I'd suggest you do:
   protected boolean processKeyBinding(KeyStroke ks, KeyEvent e, int condition, boolean pressed) {
      if (isEditing()) {
         Component editorComponent=getEditorComponent();
         editorComponent.stopCellEditing();
         return true;
      return super.processKeyBinding(ks,e,condition,pressed);
   }Ok.... now, it appears that you want to do something else also... i.e., add a new row to the table if the editing row is the last row and the editing column is the last column of the last row. You can't do that in the same thread (i.e., you must wait until the update in the current thread is completed). So, what you must do is use the SwingUtilities.InvokeLater, like this:
   protected boolean processKeyBinding(KeyStroke ks, KeyEvent e, int condition, boolean pressed) {
      if (isEditing()) {
         Component editorComponent=getEditorComponent();
         editorComponent.stopCellEditing();
         if (getEditingRow()+1==getRowCount() && getEditingColumn()+1==getColumnCount()) {
            SwingUtilities.invokeLater(new Runnable() {
               public void run() {
// put the code for adding new row here
         return true;
      return super.processKeyBinding(ks,e,condition,pressed);
   }OK?
;o)
V.V.
PS: posted code is untest but should work!

Handling keyTyped events in JTable for TAB key

In my app, I have a JTable. Some columns are non-editable.
I have attached a keyListener to the table and have overridden keyTyped() and keyReleased() methods.
In keyReleased(), I do something depending on the key code. For example: if its the VK_DELETE, I delete the row. If its some other user configured key, then I show a popup dialog where the user can enter some data, etc...
In keyTyped(), I first check if the column is one of the specific columns. Then I get the keyChar. After this, I show a dialog and pre-populate a JTextField on this dialog with that keyChar.
My issue is that 'TAB' key events arrive in keyTyped() and not in keyReleased(). As a result, the dialog is shown and the tab takes place inside the JTextfield which is incorrect.
I would like to ignore TAB keyTyped events. When I look up the keyCode in keyTyped() method, it is 0. So there is no way for me to tell what key was typed.
How can I ignore TAB events in my keyTyped() method?
thx

I now do the following to determine if TAB key has been typed
public void keyTyped(KeyEvent e) {
char c = e.getKeyChar();
if (c == KeyEvent.VK_TAB) {
Is this correct ?
Edited by: tsc on Sep 28, 2007 12:40 PM

Macbook misses some key events for a few seconds

I have noticed that for last two months or so something strange happens to my Retina MBP. Once in a couple of days it stops responding to some key events. It is like it handles only one keypress out of 4-5. Nothing seems to be wrong with the keyboard and it is not about a particular key or keys. And about 10-15 seconds later everything goes back to normal. I do not see any suspicious messages in the logs, the computer is connected to the power supply...It happens just by itself in the middle of the day, when I am typing.
Almost looks like some interrupts get lost by the system while it is busy with something else. But I have checked the load level and running processes - nothing interesting there....And whatever it is - it happens during a very short period of time.

Hi,
No, I have not returned my MBP yet. In fact, I would rather avoid doing this unless I am convinced if it is a hardware issue. And I do believe it is not. Just recently I have spent some time investigating it and I have found very stroing correlation between the moments when this happens and these messages in the kernel log:
Jan 13 10:49:54 mbp-wifi kernel[0]: Sandbox: sandboxd(96471) deny mach-lookup com.apple.coresymbolicationd
Jan 13 10:54:31 mbp-wifi kernel[0]: Sandbox: sandboxd(96499) deny mach-lookup com.apple.coresymbolicationd
Jan 13 10:54:31 mbp-wifi.home sandboxd[96499] ([96497]): mdworker(96497) deny mach-lookup com.apple.ls.boxd
Jan 13 10:54:31 mbp-wifi.home sandboxd[96499] ([96498]): mdworker(96498) deny mach-lookup com.apple.ls.boxd
Jan 13 10:56:32 mbp-wifi.home sandboxd[96504] ([96503]): mdworker(96503) deny mach-lookup com.apple.ls.boxd
Jan 13 10:56:32 mbp-wifi.home sandboxd[96504] ([96502]): mdworker(96502) deny mach-lookup com.apple.ls.boxd
And I have also noticed that my Spotlight database gets reconstructed too often, which means it gets corrupted.
From all this I conclude that it is most likely the software issue and it seems to be linked to spotlight. I saw people reporting similar things. So now I am researching on how to fix it without disabling the spotlight.
In general, I believe that the quality of Apple software is going down, it is not like 4-5 years ago And Apple does seem to care less and less about it.
If in your case it happens all the time, not just once in a while, and you see that a particular key has problems - it is possible that we are talking about the different issues and yours might be really about the keyboard.

Is it possible to handle multiple events using Jscript for a button in Apex

Hi,
I've application wherein in one of the pages for a button, I need to trigger 2 events as: 1. redirect to a new page upon 'click' of the button
2. display a set of values on 'mouse over' that button.
I'm able to handle both separately, but not in one button. I would like to know if there is any limitation in Apex that we cant handle multiple events? Currently I've put a text item near the button, and called the Jscript for mouse over event in that as a temporary workaround. Can someone let me know if this is feasible? If not any other alternative to handle this?
Thanks in advance,
gsachidh

Hi Gsachidh,
well interesting problem you're facinng. Indeed, it can't be specified using the 'Button Attributes' So we have to come up with an workaround.
A quick en dirty solution would be to specify it with the 'Optional URL Redirect options'. In a normal button, with processing on same page, this would be 'no target'. but in case of additional things to be done this can be used, using an target URL. I used this many times, in example with popUp windows for refreshing the caller object when changes are made. In your case we have to add next to the href an onmouseover event. this can be done with;
Target set to => URL
URL - target => javascript:doSubmit('<button_name>');" onMouseOver="javascript:showTooltip('tooltip');"
Here the " is the key, letting ApEx know the target (href) is doSubmit('<button_name>'), just like when no target would be specified and adding a new javascript event; onMouseOver.
Although this is a dirty solution in my opinion, it is the best i could come up with. I have another idea in how to do this, that is by adding this event dynamically with javascript with an addEvent. But i don't have an example at the moment for this scenario.
Simon
Message was edited by:
S1M0N

Reg : Cross browser issue while handling LOV event on KeyFlexFeild

Hi OA Gurus,
We are encountering issues on R12.0.6, JDev 120Rup6.
We have the following test case and code changes.
Requirement:
We have OA page where we have one KeyFlexFeild item and a normal LOV. Page items are part of one AM and LOV is in another AM.
The requirement was to make LOV dependent on keyFlexfeild. Test case is mentioned as per following flow.
1.     User changes cost center segment of Accounting Flex(Key flex) using Cost center LOV.
2.     Another LOV in the same page should be dependent on new value of cost center as modified in step 1.
Solution Implemented:
Describing in the 3 steps
1) Here the KeyFlexFeild is expense account. Whenever User changes any segment, we handle
‘lovValidate’ and ‘lovUpdate’ events on KeyFlexFeild in processFormRequest of controller.
2) Retrieve the value of cost center segment using getSegmentsQualifiedBy(), Update corresponding VO attribute of the LOV query parameter.
3) Forward the request to current page so that LOV will have modified value with updated query.
4) Forwarding to current page is must because LOV is built with another AM and will loaded only when page is built.
Issue:
This works fine on internet explorer. When trying to run the same in Mozilla we have following issue
1) User modifies one of the segments of expense account and make a tab – out
2) Now the page refresh happens
3) Now in the same page no other LOV or no other button works. He can’t click on any button for submit or cancel.
LOVs will not open even after clicking on it.
Code changes:
//Step1 – Handle LOV events
String source = pageContext.getParameter(SOURCE_PARAM);
String eventType = pageContext.getParameter(EVENT_PARAM);
if(source !=null && eventType != null) {
if(source.startsWith("Acct") && eventType.equals("lovUpdate") || eventType.equals("lovValidate") ) {
KeyFlexfield flex = (KeyFlexfield)lkff.getAttributeValue(OAWebBeanConstants.FLEXFIELD_REFERENCE);
// Step -2 Updating the corresponding VO attribute for LOV to get the modified the value
Segment[ ] segmentL = flex.getSegmentsQualifiedBy(FA_COST_CTR");
CostCenterValue = segmentL[0].getValue().getValue();
if(CostCenterValue != null ){
sampleViewObject.getCurrentRow().setAttribute("ToCostCenter",CostCenterValue);
OAFormValueBean formValueBean = (OAFormValueBean)webBean.findIndexedChildRecursive("ToCostCenter");
if(formValueBean != null)
formValueBean.setValue(pageContext, CostCenterValue);
OAMessageLovInputBean formValueBean1 = (OAMessageLovInputBean)webBean.findIndexedChildRecursive("ReceivingApprover");
if(formValueBean1 != null)
formValueBean1.setValue(pageContext, null);
else
sampleViewObject.getCurrentRow().setAttribute("ToCostCenter",null);
//Step 3 – Forward the request Current Page again
pageContext.setForwardURLToCurrentPage(null, true, ADD_BREAD_CRUMB_YES, (byte)0);
We have following questions.
a)     Solution implemented by us is correct ? or we have to implement it in another way ?
b)     Is OA version mentioned above supported on Mozilla browser version 3.x ? This issue is not occurring on Mozilla 1.x while running from JDev.
Please let us know if any additional details required.
Thanks for help in advance.
Edited by: user774130 on Dec 15, 2009 2:27 AM

Hi,
It seems that you have not noticed that this forum is not for posting product-related questions/problems....
So , this might be the correct forum....
Java Server Pages (JSP)
Sim

How to consume key events

I would like to create a subclass of TextBox that only allows numeric input. My idea was to provide my own onKeyType() handler and consume any key events that do not correspond to digits. However, I can't find any way to consume key events from further processing. How do I do this?
Are there any other suggestions how to accomplish the task of providing your own filter concerning valid key input?
/Bengt

I also wanted a kind of validators for the TextBox class of JavaFX. So I've tried solving the problem using the SwingTextField class and some Java APIs. The following is my code for a SwingTextField accepting only digits, but I do want it to be much simpler.
import java.awt.AWTEvent;
import java.awt.event.AWTEventListener;
import java.awt.event.KeyEvent;
import java.awt.Toolkit;
import javafx.ext.swing.SwingTextField;
import javafx.scene.Scene;
import javafx.stage.Stage;
import javax.swing.JComponent;
class DigitKeyEventHookListener extends AWTEventListener {
    public-init var source:JComponent;
    public override function eventDispatched( event:AWTEvent):Void {
        if (event.getSource().equals(source)) {
            var keyEvent : KeyEvent = event as KeyEvent;
            var keyCharacter = keyEvent.getKeyChar();
            var isDigit = false;
            var code = keyEvent.getKeyCode();
           if ((KeyEvent.VK_0 <= keyCharacter) and (keyCharacter <= KeyEvent.VK_9)) {
                   isDigit = true;
            if ((code ==KeyEvent.VK_DELETE) or (code ==KeyEvent.VK_BACK_SPACE)) {
                isDigit = true;
            if ((code ==KeyEvent.VK_LEFT) or (code ==KeyEvent.VK_RIGHT)) {
                isDigit = true;
           if (not isDigit) {
                keyEvent.consume();
function createSwingTextField() : SwingTextField{
    var field = SwingTextField {
        columns:12
    var listener = DigitKeyEventHookListener{
        source: field.getJTextField()
    Toolkit.getDefaultToolkit().addAWTEventListener(listener, AWTEvent.KEY_EVENT_MASK);
    return field;
Stage {
    title: "Digit Box"
    width: 200
    height: 80
    scene: Scene {
        content: createSwingTextField()
}

Help with understanding key event propagation

Hello,
I am hoping someone can help me understand a few things which are not clear to me with respect to handling of key events by Swing components. My understanding is summarized as:
(1) Components have 3 input maps which map keys to actions
one for when they are the focused component
one for when they are an ancestor of the focused component
one for when they are in the same window as the focused component
(2) Components have a single action map which contains actions to be fired by key events
(3) Key events go to the currently focused component
(4) Key events are consumed by the first matching action that is found
(5) Key events are sent up the containment hierarchy up to the window (in which case components with a matching mapping in the WHEN_IN_FOCUSED_WINDOW map are searched for)
(6) The first matching action handles the event which does not propagate further
I have a test class (source below) and I obtained the following console output:
Printing keyboard map for Cancel button
Level 0
Key: pressed C
Key: released SPACE
Key: pressed SPACE
Level 1
Key: pressed SPACE
Key: released SPACE
Printing keyboard map for Save button
Level 0
Key: pressed SPACE
Key: released SPACE
Level 1
Key: pressed SPACE
Key: released SPACE
Printing keyboard map for Main panel
Event: cancel // typed SPACE with Cancel button having focus
Event: save // typed SPACE with Save button having focus
Event: panel // typed 'C' with panel having focus
Event: panel // typed 'C' with Cancel button having focus
Event: panel // typed 'C' with Save button having focus
I do not understand the following aspects of its behaviour (tested on MacOSX although I believe the behaviour is not platform dependent):
(1) I assume that the actions are mapped to SPACE since the spacebar clicks the focused component but I don't explicitly set it?
(2) assuming (1) is as I described why are there two mappings, one for key pressed and one for key released yet the 'C' key action only has a key pressed set?
(3) assuming (1) and (2) are true then why don't I get the action fired twice when I typed the spacebar, once when I pressed SPACE and again when I released SPACE?
(4) I read that adding a dummy action with the value "none" (i.e. the action is the string 'none') should hide the underlying mappings for the given key, 'C' the my example so why when I focus the Cancel button and press the 'C' key do I get a console message from the underlying panel action (the last but one line in the output)?
Any help appreciated. The source is:
import javax.swing.*;
public class FocusTest extends JFrame {
     public FocusTest ()     {
          initComponents();
          setTitle ("FocusTest");
          setLocationRelativeTo (null);
          setSize(325, 160);
          setVisible (true);
     public static void main (String[] args) {
          new FocusTest();
private void initComponents()
     JPanel panTop = new JPanel();
          panTop.setBackground (java.awt.Color.RED);
JLabel lblBanner = new javax.swing.JLabel ("PROPERTY TABLE");
lblBanner.setFont(new java.awt.Font ("Lucida Grande", 1, 14));
lblBanner.setHorizontalAlignment (javax.swing.SwingConstants.CENTER);
          panTop.add (lblBanner);
          JPanel panMain = new JPanel ();
          JLabel lblKey = new JLabel ("Key:");
          lblKey.setFocusable (true);
          JLabel lblValue = new JLabel ("Value:");
JTextField tfKey = new JTextField(20);
JTextField tfValue = new JTextField(20);
JButton btnCancel = new JButton (createAction("cancel"));     // Add a cancel action.
JButton btnSave = new JButton (createAction("save"));          // Add a sve action.
          panMain.add (lblKey);
          panMain.add (tfKey);
          panMain.add (lblValue);
          panMain.add (tfValue);
          panMain.add (btnCancel);
          panMain.add (btnSave);
          add (panTop, java.awt.BorderLayout.NORTH);
          add (panMain, java.awt.BorderLayout.CENTER);
setDefaultCloseOperation (javax.swing.WindowConstants.EXIT_ON_CLOSE);
// Add an action to the panel for the C key.
          panMain.getInputMap (JComponent.WHEN_IN_FOCUSED_WINDOW).put (KeyStroke.getKeyStroke (java.awt.event.KeyEvent.VK_C, 0), "panel");
          panMain.getActionMap ().put ("panel", createAction("panel"));
          // FAILS ???
          // Add an empty action to the Cancel button to block the underlying panel C key action.
btnCancel.getInputMap().put (KeyStroke.getKeyStroke (java.awt.event.KeyEvent.VK_C, 0), "none");
// Print out the input map contents for the Cancel and Save buttons.
System.out.println ("\nPrinting keyboard map for Cancel button");
printInputMaps (btnCancel);
System.out.println ("\nPrinting keyboard map for Save button");
printInputMaps (btnSave);
          // FAILS NullPointer because the map contents are null ???
System.out.println ("\nPrinting keyboard map for Main panel");
// printInputMaps (panMain);
private AbstractAction createAction (final String actionName) {
     return new AbstractAction (actionName) {
          public void actionPerformed (java.awt.event.ActionEvent evt) {
               System.out.println ("Event: " + actionName);
private void printInputMaps (JComponent comp) {
     InputMap map = comp.getInputMap();
     printInputMap (map, 0);
private void printInputMap (InputMap map, int level) {
     System.out.println ("Level " + level);
     InputMap parent = map.getParent();
     Object[] keys = map.allKeys();
     for (Object key : keys) {
          if (key.equals (parent)) {
               continue;
          System.out.println ("Key: " + key);
     if (parent != null) {
          level++;
          printInputMap (parent, level);
Thanks,
Tim Mowlem

Use the [url http://forum.java.sun.com/help.jspa?sec=formatting]Code Formatting Tags so the posted code retains its original formatting.
1) In the Metal LAF the space bar activates the button. In the Windows LAF the Enter key is used to activate the button. Therefore these bindings are added by the LAF.
2) The pressed binding paints the button in its pressed state. The released binding paint the button in its normal state. Thats why the LAF adds two bindings.
In your case you only added a single binding.
3) The ActionEvent is only fired when the key is released. Same as a mouse click. You can hold the mouse down as long as you want and the ActionEvent isn't generated until you release the mouse. In fact, if you move the mouse off of the button before releasing the button, the ActionEvent isn't even fired at all. The mouse pressed/released my be generated by the same component.
4) Read (or reread) the [url http://java.sun.com/docs/books/tutorial/uiswing/misc/keybinding.html#howto]How to Remove Key Bindings section. "none" is only used to override the default action of a component, it does not prevent the key stroke from being passed on to its parent.

Handling button events in large app

I'm currently examining a large swing app, and have observed the following with regard to action events.
A number of listeners (for buttons, menu items, JLists etc.) are defined at the top of the app. These variously extend MouseAdapter or implement ActionListener, depending on the type of component whose actions they listen for.
The ButtonListener definition is as follows :
private class ButtonListener implements ActionListener
public void actionPerformed(ActionEvent event)
Object object = event.getSource();
if (object == button1)
// button1 actions
else
if (object == button2)
// button2 actions
.....etc
One instance of this listener is created in the app, and is used as the actionlistener for each button. This means that the buttonlistener is quite large (as it contains the code for each button in the app).
Is this the proper way to handle button events for an app with a large number of buttons?

Thanks for the responses.
In response to theDude : I agree that defining the action listener for each button can be useful when you can see the button definition and button action in one place; one could counter that by saying that grouping all the button actions makes it easier to examine all button actions in one place.
Setting the action command isn't really an option because the application creates panels of buttons on the fly, e.g. when notification of a new customer is received, a new panel is created with a JTextPane (customer description) and a row of buttons for "Modify", "Delete" and "Print".
Several customer panels could be in existence at the same time, so setting an action command of "Modify" would not enable one to uniquely identify which "Modify" button was pressed.
This problem is currently handled by associating the panel instance with a "Customer" class instance in a hashtable. The "Customer" class consists of a JTextPane field, and a JButton for each function. When a button is pressed, the button listener traverses up the component's parents until it reaches the panel (i.e. it loops until the parent is a key on the hashtable, at which point it can retrieve the Customer instance and check which button was pressed).
In response to KPSeal : If I understand you, I would define "ApplicationAction" separately from the main app and define extensions of it in the main app for each type of action. Would this add much value over merely defining a method for each type of action in the main app and just calling this method when the relevant button/menu item was pressed/selected?
There doesn't seem to be a universal approach to event handling, but I thought there might have been one accepted strategy when an app has large numbers of buttons (some created on the fly, ruling out action commands).

Handling Key Event

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