SaveDiscardCancelTask.execute() will run on a worker thread, but it posts a callback to run on the UI thread and then immediately goes to sleep. The UI thread callback shows the prompt, and when the user chooses their option, it sets the 'choice' member variable and wakes up the worker thread, which then completes its task and returns the user's choice.
-T On Thu, Oct 22, 2009 at 8:51 PM, Scott Lanham <li...@sael.com.au> wrote: > I don't understand your sample code fully yet but it looks like the Dialog > asking the question about saving etc is created in a new thread. > > On Fri, 23 Oct 2009 10:46:59 am Todd Volkert wrote: > > In general, the UI isn't thread safe, so all UI operations should be done > > on the UI thread. Why do you ask? > > -T > > > > On Thu, Oct 22, 2009 at 7:11 PM, Scott Lanham <li...@sael.com.au> wrote: > > > Thanks Todd, that is great. > > > > > > One question though. Is there any problem with creating a dialog in a > > > separate > > > thread to the main thread? > > > > > > On Fri, 23 Oct 2009 08:23:43 am Todd Volkert wrote: > > > > Hi Scott, > > > > > > > > First off, you can only do this in DesktopApplicationContext, since > > > > BrowserApplicationContext can't reliably prevent the applet from > > > > getting destroyed. If you are in DesktopAplpicationContext, then the > > > > very short answer is that you return true from Application.shutdown() > > > > to prevent the shutdown until the user has answered your question. > > > > Then, when they > > > > > > answer > > > > > > > your dialog (or sheet), you call DesktopApplicationContext.exit(), > and > > > > allow the shutdown at that time. > > > > > > > > The long answer is that it's kinda tricky to get right. To aid you > on > > > > > > your > > > > > > > way, I'll blindly paste snippets of the source of my Pivot app that > > > > does exactly this - you should be able to gleam what you need from > it. > > > > > > > > I've attached two snippet source files. Let me know if they don't > come > > > > through. > > > > > > > > -T > > > > > > > > On Thu, Oct 22, 2009 at 5:58 PM, Scott Lanham <li...@sael.com.au> > wrote: > > > > > Hi All, > > > > > > > > > > I am at the point in my application where during > Application.shutdown > > > > > I would > > > > > like a dialog to popup if they haven't saved their changes. The > > > > > dialog would > > > > > ask if they want to Save, Not Save, Cancel with the last cancelling > > > > > the shutdown. I am uncertain of how to approach this and was hoping > > > > > someone could > > > > > give me some guidance :-) > > > > > > > > > > Thanks, > > > > > > > > > > Scott. > >
