Assertion failed using Qt and Cocoa on MacOSX Mavericks

ROOT
1

I’m developing a program with a GUI using Qt and Root following these guidelines. Under Linux I have no problem; however under OSX Mavericks I get the following error (I compiled Root libraries with debug symbols):

This happens with Root 5.34.25 and Qt 4.8.6. I don’t know if this is a bug or a mistake of mine. I can provide further details on demand if someone is willing to help me investigating this issue.
Thanks.

2

This means the drawable (window/“pixmap”/“ximage”) was not created by ROOT == ROOT Cocoa does not support ‘alien’ windows/views. Build your ROOT with --disable-cocoa, probably, ROOT + Qt will work with XQuartz.

3

With XQuartz at least the program starts. The Qt part works fine, however Root canvas show no content and the terminal is spammed by messages like these:

4

There is no magic - if you use Qt with Cocoa plugin/Carbon - their views/windows/whatever probably have no sense in XQuartz’s world. Build Qt with xcb plugin/X11.

Windows version is lucky since HWND/HANDLE is the same thing in Qt world and ROOT world.
Pixmap/Window - are the same integers in ROOT/QT world on unixes with X11.

This does not always have to be true on other platforms. And even more - Qt4/Qt5 are very different.

5

Thanks tpochep, I’m not an expert in these things but I understand that things are too difficult for my purposes. I could cope with rebuilding Qt on OSX using X11 but my colleagues won’t ever bother with this. My Qt/Root application should work in a stock system, and the only thing that I could ask them is to rebuild Root with some options. Is there any chance that this issue with Cocoa and Qt/Root will ever be addressed by the Root devs? Otherwise my application is on a dead end on OSX…

6

No, I’m afraid, the answer is ‘no’.

7

Hi,

We are using Qt in our gui together with GSI QtRoot interface.
For a long time it was no problem to compile it under Mac.
But this only was possible when Qt was compiled with X11 option (qt4-x11).
Such package was provided via macports.
Unfortunately, it is no longer available.
Just type in google ‘macports qt4-x11’.
Without such option QtRoot interface does not works.

Regards,
Sergey

8

Hi Sergey, I’m currently trying to build Qt with the -carbon option. Will this make Qt use XQuartz? There is no clear reference on the web about this, at least none that I’ve been able to find.

9

Sorry, I am not active Mac user, therefore have no idea how good XQuartz implements X11 and
could one use it for QtRoot interface.