My application requires a dialog box and a parent window, from the window proc of the parent window I'm trying to draw on the dialog box. How might I do this?

Thank you for reading :)

Recommended Answers

All 11 Replies

parent window shouldn't be trying to draw on the dialog box -- let the dialog box do all the drawing.

So is it not possible?:)

Thanks for the reply!

To help I will explain further, from the wm_paint handler in my parent window proc call textout in order to display text on the dialog box in my program. :D

I'm not saying it's impossible, but normally the parent will send a message to dialog so that dialog can update the text in the dialog's window. You can set up private messages to do that.

Ok sorry if I'm using up too much of your time, but how do I use drawing command in a thread and then use _beginthread function during the wm_paint handler of a dialog box I have tried but I can't seem to get it to display anything? :)

Thanks for the reply!

You can't -- drawing must be done in the same thread as the dialog box. If you don't want the dialog box in the same thread as the parent then either put the entire dialog box in another thread or create a modeless dialog box.

Why Windows Threads Are Better Than POSIX Threads (e.g. CreateThread() better than _beginthread() )

What I'm trying to do is have my dialog box appear when a menu item is pressed (I have done that) but then a thread containing textout function to display text on the dialog box begins but the text isn't displayed, could this be a defect of _beginthread?

Thanks for the reply :)

could this be a defect of _beginthread?

No -- that's how Microsoft designed the api.

So I'm not able to add gdi functions to threads that begin in a dialog box?

Thanks for the reply :)

That's right -- drawing must be done in the same thread as the window or dialog box.

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.