Problem when manipulating QT window geometry

[Marcus Nolte]

Hello Everyone,

I am currently experimenting a little with Genode 14.08.
When playing around in Qt5, I encountered some problems when trying to 
change the geometry of a QMainWindow.
I have an additional Genode::Thread running, which can trigger a 
geometry-change of the application's main window by methods provided by 
the MainWindow.

When a change of the window's geometry is triggered, it seems as if the 
window-decorations are properly resized, but the QtWindow underneath is 
kept at its original size. Additionally, the thread which triggers the 
geometry-change is blocked (this holds true for the Genode::Thread, as 
well as for a QThread).

Resizing the window with the mouse works properly.

I took a look at the Nitpicker Qt-Plugin, where I noticed two things:
1. - There is some unused code in qnitpickerplatformwindow.cpp in 
QNitpickerPlatformWindow::handle_events().
Until now I did not dig into the Window_slave_policy, but the inactive 
code segment looks to me, as if it should change the QtWindow's geometry.

2. - The Processing seems to stop somewhere before returning the 
framebuffer of the the PlatformWindow when detaching / attaching it from 
/ to the rm_ssession.

Since I'm not quite familiar with all the internal Nitpicker / Qt stuff, 
it would be great if anyone with a little more experience could provide 
some help. ;-)
- Or am I even trying something which is not intended?

Cheers
Marcus