I am saving A JTable to my SQL Database. No problems with that. However, I wanted to make some kind of dialog that stays on the screen while data from the database is being loaded. I used a JDialog with a JOptionPane:
final JOptionPane pane = new JOptionPane("Loading", JOptionPane.INFORMATION_MESSAGE,
JOptionPane.DEFAULT_OPTION, null, new Object[] {}, null);
final JDialog dialog = new JDialog();
dialog.setTitle("Loading");
dialog.setModal(true);
dialog.setContentPane(pane);
dialog.setDefaultCloseOperation(JDialog.DO_NOTHING_ON_CLOSE);
dialog.pack();
dialog.setLocationRelativeTo(null);
dialog.setVisible(true);
Now, I want the dialog to close as soon as my SQL Statement is executed, however as it seems the dialog keeps the Statement from being executed, as the thread is blocked by it apparently. So, how do I execute my SQL statements while the Dialog is showing and then closes itself after the statement is executed?
I guess you can add a propertchange listener to your code.
Found a similar question: [Java Swing - Close JDialog from external Thread1
Answer in that post is as follows:
Stopping Automatic Dialog Closing
By default, when the user clicks a JOptionPane-created button, the
dialog closes. But what if you want to check the user's answer before
closing the dialog? In this case, you must implement your own property
change listener so that when the user clicks a button, the dialog does
not automatically close.
DialogDemo contains two dialogs that implement a property change
listener. One of these dialogs is a custom modal dialog, implemented
in CustomDialog, that uses JOptionPane both to get the standard icon
and to get layout assistance. The other dialog, whose code is below,
uses a standard Yes/No JOptionPane. Though this dialog is rather
useless as written, its code is simple enough that you can use it as a
template for more complex dialogs.
Besides setting the property change listener, the following code also
calls the JDialog's setDefaultCloseOperation method and implements a
window listener that handles the window close attempt properly. If you
do not care to be notified when the user closes the window explicitly,
then ignore the bold code.
final JOptionPane optionPane = new JOptionPane(
"The only way to close this dialog is by\n"
+ "pressing one of the following buttons.\n"
+ "Do you understand?",
JOptionPane.QUESTION_MESSAGE,
JOptionPane.YES_NO_OPTION);
final JDialog dialog = new JDialog(frame,
"Click a button",
true);
dialog.setContentPane(optionPane);
dialog.setDefaultCloseOperation(
JDialog.DO_NOTHING_ON_CLOSE);
dialog.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent we) {
setLabel("Thwarted user attempt to close window.");
}
});
optionPane.addPropertyChangeListener(
new PropertyChangeListener() {
public void propertyChange(PropertyChangeEvent e) {
String prop = e.getPropertyName();
if (dialog.isVisible()
&& (e.getSource() == optionPane)
&& (prop.equals(JOptionPane.VALUE_PROPERTY))) {
//If you were going to check something
//before closing the window, you'd do
//it here.
dialog.setVisible(false);
}
}
});
dialog.pack();
dialog.setVisible(true);
int value = ((Integer)optionPane.getValue()).intValue();
if (value == JOptionPane.YES_OPTION) {
setLabel("Good.");
} else if (value == JOptionPane.NO_OPTION) {
setLabel("Try using the window decorations "
+ "to close the non-auto-closing dialog. "
+ "You can't!");
}
I have an application with a JFrame containing text fields. When text in a field is modified, and the field gets a focusLost event, it immediately writes its contents to an external database.
However, if the user quits the application while a field is still focused, the focusLost message is not sent and the modified data is not saved.
How can I force the loss of focus on a field, perhaps in a windowClosing method in my WindowListener? I tried using requestFocusInWindow() in that method, but it did not help.
Why not just call the same method that writes the contents to the external database from within the windowClosing method of your window listener?
#Override
public void windowClosing(WindowEvent e) {
// call write to DB method
System.exit(0);
}
Another way of going about it:
Change the setDefaultCloseOperation of the JFrame to DO_NOTHING_ON_CLOSE, and show a confirmation dialog when the user wants to close the window. The dialog will receive focus, triggering the focusLost method on the textfield's FocusListener.
frame.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
frame.addWindowListener(new WindowAdapter() {
#Override
public void windowClosing(WindowEvent e) {
int result = JOptionPane
.showConfirmDialog(null, "Are you sure?",
"Confirm exit", JOptionPane.YES_NO_OPTION);
if(result == 0) {
System.exit(0);
}
}
}
});
(Note: If you go with this method, be sure you don't exit in the middle of writing to the DB.)
Pending a better answer that may be forthcoming from someone more experienced that I am, here's what I'm doing.
In my windowClosing() method in my WindowListener, I put:
dispatchEvent(new FocusEvent(getFocusOwner(), FocusEvent.FOCUS_LOST));
How can I detect the java window closing if it was forced by clicking on windows taskbar -> close window?
I've found that the window to close receives the WINDOW_CLOSING event which is possible to process by adding windowListener. But in this case window would being closed anyway. Is there any way to prevent the window closing?
You can set the default close operation to DO_NOTHING_ON_CLOSE and ask the user for a confirmation instead. It's a pretty common practice even if you want to close the frame through the X button, key combination (i.e.: ALT + F4) or any method to close a window:
JFrame frame = new JFrame("Welcome!");
frame.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
frame.addWindowListener(new WindowAdapter() {
#Override
public void windowClosing(WindowEvent e) {
int option = JOptionPane.showConfirmDialog(null, "Do you really want to exit?");
if (option == JOptionPane.OK_OPTION) {
e.getWindow().dispose();
}
}
});
To prevent window closing you should call
setDefaultCloseOperation(WindowConstants.DO_NOTHING_ON_CLOSE)
on your JFrame instance and then implement your alternative closing procedure via windowListener.
I need to stop the default operation of window being closed when red x mark is clicked on the swing window. I am using the JDialog and adding WindowsListener to it to capture the WindowClosing event, there I decide whether to dispose JDialog or to not dispose it, I am also setting the following:
setDefaultCloseOperation(JDialog.DO_NOTHING_ON_CLOSE);
But still when I click on the red x mark, the window closes. Any ideas?
Adding Window listener to the JDialog gave me the power to handle the window actions and I works fine in my application.
You can try creating a WindowListener and do nothing when the close buttion is clicked.
jdialog.addWindowListener(new WindowAdapter()
{
public void windowClosed(WindowEvent e)
{
}
public void windowClosing(WindowEvent e)
{
}
});
What's the correct way to get a JFrame to close, the same as if the user had hit the X close button, or pressed Alt+F4 (on Windows)?
I have my default close operation set the way I want, via:
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
It does exactly what I want with the aforementioned controls. This question isn't about that.
What I really want to do is cause the GUI to behave in the same way as a press of X close button would cause it to behave.
Suppose I were to extend WindowAdaptor and then add an instance of my adaptor as a listener via addWindowListener(). I would like to see the same sequence of calls through windowDeactivated(), windowClosing(), and windowClosed() as would occur with the X close button. Not so much tearing up the window as telling it to tear itself up, so to speak.
If you want the GUI to behave as if you clicked the X close button then you need to dispatch a window closing event to the Window. The ExitAction from Closing An Application allows you to add this functionality to a menu item or any component that uses Actions easily.
frame.dispatchEvent(new WindowEvent(frame, WindowEvent.WINDOW_CLOSING));
setVisible(false); //you can't see me!
dispose(); //Destroy the JFrame object
Not too tricky.
If by Alt-F4 or X you mean "Exit the Application Immediately Without Regard for What Other Windows or Threads are Running", then System.exit(...) will do exactly what you want in a very abrupt, brute-force, and possibly problematic fashion.
If by Alt-F4 or X you mean hide the window, then frame.setVisible(false) is how you "close" the window. The window will continue to consume resources/memory but can be made visible again very quickly.
If by Alt-F4 or X you mean hide the window and dispose of any resources it is consuming, then frame.dispose() is how you "close" the window. If the frame was the last visible window and there are no other non-daemon threads running, the program will exit. If you show the window again, it will have to reinitialize all of the native resources again (graphics buffer, window handles, etc).
dispose() might be closest to the behavior that you really want. If your app has multiple windows open, do you want Alt-F4 or X to quit the app or just close the active window?
The Java Swing Tutorial on Window Listeners may help clarify things for you.
Stop the program:
System.exit(0);
Close the window:
frame.dispose();
Hide the window:
frame.setVisible(false);
If you have done this to make sure the user can't close the window:
frame.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
Then you should change your pullThePlug() method to be
public void pullThePlug() {
// this will make sure WindowListener.windowClosing() et al. will be called.
WindowEvent wev = new WindowEvent(this, WindowEvent.WINDOW_CLOSING);
Toolkit.getDefaultToolkit().getSystemEventQueue().postEvent(wev);
// this will hide and dispose the frame, so that the application quits by
// itself if there is nothing else around.
setVisible(false);
dispose();
// if you have other similar frames around, you should dispose them, too.
// finally, call this to really exit.
// i/o libraries such as WiiRemoteJ need this.
// also, this is what swing does for JFrame.EXIT_ON_CLOSE
System.exit(0);
}
I found this to be the only way that plays nice with the WindowListener and JFrame.DO_NOTHING_ON_CLOSE.
Exiting from Java running process is very easy, basically you need to do just two simple things:
Call java method System.exit(...) at at application's quit point.
For example, if your application is frame based, you can add listener WindowAdapter and and call System.exit(...) inside its method windowClosing(WindowEvent e).
Note: you must call System.exit(...) otherwise your program is error involved.
Avoiding unexpected java exceptions to make sure the exit method can be called always.
If you add System.exit(...) at right point, but It does not mean that the method can be called always, because unexpected java exceptions may prevent the method from been called.
This is strongly related to your programming skills.
** Following is a simplest sample (JFrame based) which shows you how to call exit method
import java.awt.event.*;
import javax.swing.*;
public class ExitApp extends JFrame
{
public ExitApp()
{
addWindowListener(new WindowAdapter()
{
public void windowClosing(WindowEvent e)
{
dispose();
System.exit(0); //calling the method is a must
}
});
}
public static void main(String[] args)
{
ExitApp app=new ExitApp();
app.setBounds(133,100,532,400);
app.setVisible(true);
}
}
Not only to close the JFrame but also to trigger WindowListener events, try this:
myFrame.dispatchEvent(new WindowEvent(myFrame, WindowEvent.WINDOW_CLOSING));
Best way to close a Swing frame programmatically is to make it behave like it would when the "X" button is pressed. To do that you will need to implement WindowAdapter that suits your needs and set frame's default close operation to do nothing (DO_NOTHING_ON_CLOSE).
Initialize your frame like this:
private WindowAdapter windowAdapter = null;
private void initFrame() {
this.windowAdapter = new WindowAdapter() {
// WINDOW_CLOSING event handler
#Override
public void windowClosing(WindowEvent e) {
super.windowClosing(e);
// You can still stop closing if you want to
int res = JOptionPane.showConfirmDialog(ClosableFrame.this, "Are you sure you want to close?", "Close?", JOptionPane.YES_NO_OPTION);
if ( res == 0 ) {
// dispose method issues the WINDOW_CLOSED event
ClosableFrame.this.dispose();
}
}
// WINDOW_CLOSED event handler
#Override
public void windowClosed(WindowEvent e) {
super.windowClosed(e);
// Close application if you want to with System.exit(0)
// but don't forget to dispose of all resources
// like child frames, threads, ...
// System.exit(0);
}
};
// when you press "X" the WINDOW_CLOSING event is called but that is it
// nothing else happens
this.setDefaultCloseOperation(ClosableFrame.DO_NOTHING_ON_CLOSE);
// don't forget this
this.addWindowListener(this.windowAdapter);
}
You can close the frame programmatically by sending it the WINDOW_CLOSING event, like this:
WindowEvent closingEvent = new WindowEvent(targetFrame, WindowEvent.WINDOW_CLOSING);
Toolkit.getDefaultToolkit().getSystemEventQueue().postEvent(closingEvent);
This will close the frame like the "X" button was pressed.
If you really do not want your application to terminate when a JFrame is closed then,
use : setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
instead of : setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Here's a synopsis of what the solution looks like,
myFrame.dispatchEvent(new WindowEvent(myFrame, WindowEvent.WINDOW_CLOSING));
This examples shows how to realize the confirmed window close operation.
The window has a Window adapter which switches the default close operation to EXIT_ON_CLOSEor DO_NOTHING_ON_CLOSE dependent on your answer in the OptionDialog.
The method closeWindow of the ConfirmedCloseWindow fires a close window event and can be used anywhere i.e. as an action of an menu item
public class WindowConfirmedCloseAdapter extends WindowAdapter {
public void windowClosing(WindowEvent e) {
Object options[] = {"Yes", "No"};
int close = JOptionPane.showOptionDialog(e.getComponent(),
"Really want to close this application?\n", "Attention",
JOptionPane.YES_NO_OPTION,
JOptionPane.INFORMATION_MESSAGE,
null,
options,
null);
if(close == JOptionPane.YES_OPTION) {
((JFrame)e.getSource()).setDefaultCloseOperation(
JFrame.EXIT_ON_CLOSE);
} else {
((JFrame)e.getSource()).setDefaultCloseOperation(
JFrame.DO_NOTHING_ON_CLOSE);
}
}
}
public class ConfirmedCloseWindow extends JFrame {
public ConfirmedCloseWindow() {
addWindowListener(new WindowConfirmedCloseAdapter());
}
private void closeWindow() {
processWindowEvent(new WindowEvent(this, WindowEvent.WINDOW_CLOSING));
}
}
Based on the answers already provided here, this is the way I implemented it:
JFrame frame= new JFrame()
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
// frame stuffs here ...
frame.dispatchEvent(new WindowEvent(frame, WindowEvent.WINDOW_CLOSING));
The JFrame gets the event to close and upon closing, exits.
You have to insert the call into the AWT message queue so all the timing happens correctly, otherwise it will not dispatch the correct event sequence, especially in a multi-threaded program. When this is done you may handle the resulting event sequence exactly as you would if the user has clicked on the [x] button for an OS suppled decorated JFrame.
public void closeWindow()
{
if(awtWindow_ != null) {
EventQueue.invokeLater(new Runnable() {
public void run() {
awtWindow_.dispatchEvent(new WindowEvent(awtWindow_, WindowEvent.WINDOW_CLOSING));
}
});
}
}
I have tried this, write your own code for formWindowClosing() event.
private void formWindowClosing(java.awt.event.WindowEvent evt) {
int selectedOption = JOptionPane.showConfirmDialog(null,
"Do you want to exit?",
"FrameToClose",
JOptionPane.YES_NO_OPTION);
if (selectedOption == JOptionPane.YES_OPTION) {
setVisible(false);
dispose();
} else {
setDefaultCloseOperation(javax.swing.WindowConstants.DO_NOTHING_ON_CLOSE);
}
}
This asks user whether he want to exit the Frame or Application.
setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
Posting what was in the question body as CW answer.
Wanted to share the results, mainly derived from following camickr's link. Basically I need to throw a WindowEvent.WINDOW_CLOSING at the application's event queue. Here's a synopsis of what the solution looks like
// closing down the window makes sense as a method, so here are
// the salient parts of what happens with the JFrame extending class ..
public class FooWindow extends JFrame {
public FooWindow() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(5, 5, 400, 300); // yeah yeah, this is an example ;P
setVisible(true);
}
public void pullThePlug() {
WindowEvent wev = new WindowEvent(this, WindowEvent.WINDOW_CLOSING);
Toolkit.getDefaultToolkit().getSystemEventQueue().postEvent(wev);
}
}
// Here's how that would be employed from elsewhere -
// someplace the window gets created ..
FooWindow fooey = new FooWindow();
...
// and someplace else, you can close it thusly
fooey.pullThePlug();
If you do not want your application to terminate when a JFrame is closed,
use:
setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE)
instead of:
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
From the documentation:
DO_NOTHING_ON_CLOSE (defined in WindowConstants): Don't do anything; require the program to handle the operation in the windowClosing method of a registered WindowListener object.
HIDE_ON_CLOSE (defined in WindowConstants): Automatically hide the frame after invoking any registered WindowListener objects.
DISPOSE_ON_CLOSE (defined in WindowConstants): Automatically hide and dispose the frame after invoking any registered WindowListener objects.
EXIT_ON_CLOSE (defined in JFrame): Exit the application using the System exit method. Use this only in applications.
might still be useful:
You can use setVisible(false) on your JFrame if you want to display the same frame again.
Otherwise call dispose() to remove all of the native screen resources.
copied from Peter Lang
https://stackoverflow.com/a/1944474/3782247