Solved Desktop Qt Quick application goes full black screen via TeamViewer

[KroMignon]

Hi all,

I am facing a strange issue and need some help.
I have developed an Qt Application base on Qt Quick/QML (Qt 5.4.2) which runs on several embedded system. Some of them are WindowsXP base, some Windows7 Embedded.

For Windows XP systems, I can connect to my device with TeamViewer (version 10.0.47484 with premium licence) and all works as expected, I see the remote screen and I can interact with (click, etc.)
But for Windows7 systems, I only see a black screen. I can click and this will click on the HMI but I am blind! That's very bad for customer support!

I have found this bug report on Qt IO https://bugreports.qt.io/browse/QTBUG-47975 but this seems not be be relevant for me.
Nothing changes :(

I have also a QWidget Application (splash screen application), for which TeamViewer works fine with Windows XP and Windows 7.

Any suggestion for this issue?
What is the root case of this issue?

Best regards

Fabrice

[raven-worx]

@KroMignon
This may be very relevant to the used TeamViewer version (on host and client). See this

[KroMignon]

@raven-worx
Yes I am aware about this, I use same version on host and client (with valid licence).
This is a quiet old version, which works fine with WindowsXP as host.
With Windows7: Qt Widget application works, but not QML!
Any idea why?

[raven-worx]

@KroMignon
You can also try the suggestion in this comment

Anyway this is rather a TeamViewer related issue than an issue of Qt. Seems they have issues with transferring OpenGL windows.
You can also try more recent version, if this bug is already fixed by the TeamViewer team.

Is your application using ANGLE or OpenGL?

[KroMignon]

@raven-worx
I have also test the Registry Key changes, but doesn't have any impact.
By the way, I just realize that the XP build of my application is using ANGLE (because OpenGL is not supported) and Windows7 is using OpenGL.
By forcing Windows7 to use ANGLE, TeamViewer is working also with Windows7 :)

QCoreApplication::setAttribute(Qt::AA_UseOpenGLES);
qputenv("QT_OPENGL", "angle");
qputenv("QT_ANGLE_PLATFORM", "d3d9");

Thanks a lot for your time

Regards