QDockWidget freezes desktop when undocking

**pdolbey** · 8th March 2007, 11:12

I'm just posting to see if anyone has ever seen strange (i.e. inconsistent) freezing of the desktop when undocking a QDockWidget from a QMainWindow. It happens on my app, but not immediately and can be unfrozen with a Crtl-Alt-Del. My GUI is based on the MonkeyStudio MainUi.ui layout, and that suffers from the same problem as well.

I'm using Qt 4.2.2 open source / VS2005 to link to OpenCascade.

Pete

**No-Nonsense** · 8th March 2007, 12:09

I have exactly the same issue with QDockWidget as you noticed. Also with unlocking with Ctrl+Alt+Del (not killing the process). Moving the DockWidget afterwards freezes it again.
Worst: It happened the first time to me while giving a presentation of my work in progress application at my University.

I am using Qt 4.2.2 with MinGW under Windows XP Professional.

I could not identify any way to reproduce this "effect", but when it occurs one time in a session it will then occur always until rebooting Windows.

It must be a bug in Qt, because after it occured once, it occurs also with Qt Designer or other Trolltech Qt Apps/Examples.

[EDIT]
I just figured out that it will happen on my IBM ThinkPad after resuming Windows from Standby.
I had my Laptop in Standby just before the presentation to conserve battery and be ready withing seconds.

[EDIT2]Hmm this does not always work... and sometimes it works again after some time... ?![/EDIT2]
[/EDIT]

-Jens

**pdolbey** · 8th March 2007, 18:37

And I think I've managed to unblock the freezing in the past by forcing a recompile of QtCore(d).dll/QtGui(d).dll - but it might have been a coincidence.

Pete

**TheKedge** · 9th March 2007, 10:34

I had that effect too. It was very reproducable. If I hit ctrl-alt-del the dock unfreezed and was freely movable and dockable. It happened again on undocking.

I think the update to 4.2.3 cured it.

K