Why do we need IsDialogMessage at all?

re: Why do we need IsDialogMessage at all?

alv — Tue, 17 Apr 2012 09:50:17 GMT

Thanks for the explanation! I also see now that I formulated my question in a misleading way; instead of 'has focus' I should've written 'active'. Let me explain: This question came up when I was to develop and add-on to a somewhat large software suite, and part of the project was displaying a modeless dialog. I didn't have access to the main message loop (not even read-only access to the source code), and because of other constraints having my own message loop in a separate thread or process wasn't feasible either. Therefore, I had to reimplement the functionality of IsDialogMessage inside the dialog. I would've been very happy if there had been some way of telling Windows 'Hey, here is my modeless dialog, please incorporate it in some magical way to the message loop', and of course deregister it afterwards - for example when handling the WM_ACTIVATE message.

re: Why do we need IsDialogMessage at all?

Andrew — Mon, 16 Apr 2012 17:37:14 GMT

Sometimes I skip an entry since it seems so high above my head in Windows API world, but I gave this one a shot and learned something interesting about Windows and events in general :) I'll take this lesson with me.

re: Why do we need IsDialogMessage at all?

Joshua — Mon, 16 Apr 2012 15:15:47 GMT

Wow, I reinvented IsDialogMessage once.

re: Why do we need IsDialogMessage at all?

Random832 — Mon, 16 Apr 2012 14:49:15 GMT

I think this misconception may be in some part based on the HTML event model, where inner "controls" [elements], like the OK button, naturally pass the event on to the parent if they do not handle it themselves. (or the other HTML event model, where the parent control is always given all events and can choose to handle it itself or give it to the relevant child element - in either case, nothing special has to happen for the dialog to handle "tab", since the button clearly isn't interested in it.)