I am creating a Transliterating tool in Java. It's almost complete.
Here is the screenshot.
I am using JWindow for dropdown, which must be focusable for some reason.
As, user can write in one input only at one time. I've created this window static, so all Text components use the same instance instead of creating new one.
Problem occurs, when I work in more than one window. It works fine unless both window are showing on screen. But when owner window of this dropdown window is closed, dropdown window is not focusable anymore.
As Javadoc of JWindow(Window owner) constructor says:
Creates a window with the specified owner window. This window will not be focusable unless its owner is showing on the screen. If owner is null, the shared owner will be used and this window will not be focusable.
So, how can I create a static, focusable window, that is shared by all components in different windows.
Don't use a JWindow.
Instead you can use a non decorated JDialog. Then you won't have the focus problem.
Edit:
You can prevent the dialog from initially getting focus when you make it visible by using code like:
dialog.setWindowFocusableState(false);
dialog.setVisible(true);
dialog.setWindowFocusableState(true);
Related
I'm new to Java and Swing. I created a jframe and I added a menubar and MenuItem in it.
On clicking a menu item, a jdialog should open. Now the jdialog has a jtextfield in it and a jlabel. Now the problem for me is 'when dialog is opened for first time, the textfield is empty and thats correct. Now i close the jdialog and i open it again but now instead of getting an empty textfield in jdialog, i get the data entered previously' which is not what should happen as the jdialogs 'default close operation' property is set to 'dispose'. but that is not happening for me...
I dont know what i'm doing wrong. I have never tried applet/swing before in any other way (consider this as my first demo learning programme)
Second Image here
The JTextField is retaining it's value because it isn't being affected by the JDialog closing, instead it is being hidden as it's parent (the JDialog) is invisible
Setting the dialog to dispose isn't re-initialising the child components, so they keep their values. Some additional information on this behaviour is available here:
JDialog setVisible(false) vs dispose()
JDialog
One way you can prevent / control this is by "informing" the dialog to wipe the textfield as it is closing by adding a WindowEvent and providing the necessary functionality in the windowClosing() method
Netbeans gui-builder will generate this for you with the following:
Right click Dialog
Events
Window
WindowClosing
Providing:
private void jDialog1WindowClosing(java.awt.event.WindowEvent evt) {
// TODO add your handling code here:
}
In which you can add: textfield.setText(""); to clear the textfield
Another approach is to create your own dialog and setting up the components in the constructor. As creating a new instance will contain the components with their default values, effectively resetting it
Im trying to make a java program that will popup/notify me to stop what I am currently doing and do something. more like a reminder. My question is how will I make a pop up in java.
I found this docs, but dont know how to implement for the parent component.
JOptionPane.showMessageDialog(??,"this is a modal dialog.");
The answer depends, do you have a parent component (like a JFrame or other component) or are you simply display the JOptionPane independently?
If you are simply displaying the JOptionPane independently, you can simply pass it null.
If you are displaying the JOptionPane as part of a large application, with windows and other components, you can simply pass it a reference of what ever component you want the JOptionPane to displayed relative to, such as the window or most accessible container/component
The parent argument (if supplied) simply allows the dialog to act as a modal (blocking) dialog for the window which contains the supplied component. This requires the user to have to dismiss the dialog before they can continue to interact with the parent window/component
Take a closer look at How to Make Dialogs for more details
I've got a JDialog that's created and set to visible whenever the button is clicked.
My problem is that the button keeps the focus and doesn't give it to the JDialog.
Is this a normal behaviour or there's something wrong going on ?
JDialogs aren't modal (are "modeless") by default:
Creates a modeless dialog without a title and without a specified Frame owner.
Try constructing it as:
new JDialog(owner, title, ModalityType.APPLICATION_MODAL);
(Or the equivalent super() call if you're subclassing JDialog. Or whichever modality type you want.)
Try using dialog.requestFocus() if dialog is the newly created JDialog.
See requestFocus() or requestFocusInWindow() for more information.
We have an application which, as its first UI action, displays a modal JDialog without a parent frame.
public LoginDialog(Frame owner, Config config, Object... params) {
super((Frame)null, true);
It unfortunately has the annoying characteristic that when it appears, although it comes to the front, it does not grab the focus.
So the user, after launching the application by double-clicking on the start menu, has to use the mouse to select the "login" dialog and type in information.
Is there a way to make this JDialog grab the focus when it appears in the front?
I've tried calls to "requestFocus" before, after and via invokeLater "during" the call to setVisible(true) - but none of these seems to have any effect.
How do we make a modal dialog grab the focus?
UPDATE: The issue was the code used to try to present a background "wait window". This window was displayed "behind" the login dialog as a hack so that when the dialog disappeared the user would see the "Please wait" message. As it was the first window created by the application, it got the focus. I am not sure if there would have been a way to make the dialog gain the focus again inside the event dispatch thread with this hack - but I fixed it by un-hacking it and doing things properly.
First, it a little strange that modal dialog is parent-less. The point in modal dialog is that it is displayed on its parent and does not allow to access parent.
So, the first recommendation is to make it non-modal. I believe it will work.
BTW I have just tried to create such dialog and have not problems with focus. Try probably to simplify your code:
JDialog d = new JDialog();
d.setSize(200, 200);
d.setVisible(true);
This works for me and I believe will work for you. Now start changing this simple code towords your real application code. At some point it will stop working and you will see where the problem is.
If nothing helps try to use the trick I described in this article. Look for title "Portable window activation". I hope it will help.
See Dialog Focus for a potential fix using a RequestFocusListener. I have used it successfully for setting focus in JOptionPane dialogs.
1) you have to create JDialog contents and showing container wrapped inside invokeLater()
or best and safiest way is
2) you have to set for ModalityTypes or Modal for parent
3) only one from containers could be Modal in applications lifecycle
I have a general question. I would like to have a window containing some buttons, radio buttons, text fields and so on. So, user can do something (write text, select options and press buttons). As the result of the user activity window should change it structure/appearance some element should disappear and some appear.
How do I program such "updates"? Should I close an old window and open a new one or I can modify content of window without closing it?
After adding your components or such, calling revalidate() on your container will do the updates