Is creating QGLWidget with a non-visible parent resulting failed window creation a bug or a feature?

fred741 · wrote on 27 Nov 2013, 09:09

Hi all!

I found a tricky bug. Or maybe i create widget in a wrong way, i don't know.
When I try to create an QGLWidget with a parent which is yet not visible, i get the "Cannot create a top-level child window" error. It is originated from the CreateWindowEx function, because the parent widget has no window handle yet, therefor it seems that QGLContext is invalid and can't compile shaders at that time.

Is it a bug and should i report it or i am using something in the wrong order? Any suggestion?

Ps. I am using Qt 5.1.1 and MS Studio 2012. It worked fine with Qt 4.8

SGaist · wrote on 27 Nov 2013, 23:17

Hi,

I think you should bring this question to the interest mailing list, you'll find Qt's developer/maintainers there (this forum is more user oriented)

Maybe also check the "bug report system":http://bugreports.qt-project.org to see whether there's something about it in there

fred741 · wrote on 28 Nov 2013, 07:38

I'll try, thank you.

fred741 · wrote on 9 Dec 2013, 09:53

If someone has a similiar problem, it's a bug.
Related to these reported bugs:
https://bugreports.qt-project.org/browse/QTBUG-31451
https://bugreports.qt-project.org/browse/QTBUG-35342

There is a workaround on windows: creating the QGLWindow with NULL parent is somewhat solves the shader compilation.