in which thread shoud I use dialogs?
Marteno Rodia
An old Swing's rule says that all the UI operations should be carried
out in the event-dispatching thread, and other operations should be
done in other threads. I have written a GUI application which uses
multiple threads. Among them, there is a SwingWorker thread which can
inform user about an error, using a dialog for this purpose. Following
the aforementioned rule, I don't create the dialog in the SwingWorker
thread, but I put a new Runnable object in the Events' Queue.
In such context, I'm facing a great doubt: what if the dialog waited
for user's input? (some dialogs can do this, e.g. file chosers).
Wouldn't they blocked the event-dispatching thread?
regards,
Marcin
Lew
No. Classes like JDialog are designed to work with other objects on the EDT.
Modal dialogs block certain activities to the user, such as switching to a
different frame, but Swing does that by managing its own internal state. How
it ignores or eats the particular events can be a black box to us as
programmers. If we put our GUI on the EDT, Swing takes care of the rest.
Googling shows that this question is a FAQ. I didn't find in a quick search
whether Swing just handles modality in its main event loop or spawns a
hijacking thread. ISTR reading somewhere, somewhen that it's the latter.
--
Lew
Lew
> An old Swing's rule says that all the UI operations should be carried
Please do not multipost.
--
Lew