Re: JDialogs launched outside the Event-Dispatch Thread

From:

Daniel Pitts <newsgroup.spamfilter@virtualinfinity.net>

Newsgroups:

comp.lang.java.programmer

Date:

Mon, 10 May 2010 14:28:06 -0700

Message-ID:

<HT_Fn.458$Ak3.182@newsfe16.iad>

On 5/7/2010 7:55 AM, Lew wrote:

Marcin Rodzik wrote:

Being aware of what has been said<http://ow.ly/1I50nhttp://ow.ly/1I50J>
I'd like to ask explicitly: what should I do if I want to display some
information to the user in a Swing GUI app using a JDialog? I know
dialogs are event-driven so that execution of the thread which
requested displaying the dialog stops, but other currently fired
events are still handled.

The thing I don't know and I'd like to is: should I create a Runnable
object and schedule it for execution:

SwingUtilities.invokeAndWait(new Runnable() {
   @Override
   public void run() {
     /* display the dialog here */
   }

});

Usually the JDialog is raised in response to an event already on the
dispatch thread, but using invokeAndWait() or invokeLater() is fine if
you're already on the EDT.

I don't know why you'd prefer invokeAndWait() over invokeLater().

invokeAndWait must *not* be called from the EDT.
One would prefer invokeAndWait if the caller wants to be sure the event
is fully processed before continuing.

Depends on whether you really mean for the caller to wait for the
dialog.

Which is a common (if misguided) idiom.

In view code, it makes sense, but if you put it in model/controller
code, you are likely to run into huge problems later.

--
Daniel Pitts' Tech Blog: <http://virtualinfinity.net/wordpress/>