Previewing a stack widget dialog

**mikeh** · 27th September 2006, 10:49

I am using the new Windows version of Qt Designer v4.1.1 and am having a problem previewing a stack widget dialog.

When I preview a simple dialog, in XP Windows style say, it gets placed in the top left-hand corner of the screen with no title bar or title bar controls. It displays correctly and pressing ESC closes it. Is this the correct behaviour?

When I do this with a typical 'settings' dialog comprising a listview of choices and a widget stack it displays alright and responds to the change stack page controls but ESC does nothing and the whole thing hangs. The only way out is to kill the Designer application task.

I am using a Matrox millenium 650 graphics card running two monitors in DualHead mode; this might be significant.

Can anyone help with this?

**jacek** · 27th September 2006, 15:48

Originally Posted by mikeh

Is this the correct behaviour?

I don't think so. Check if the same thing happens with Qt 4.1.4.

**mikeh** · 28th September 2006, 15:21

Originally Posted by jacek

I don't think so. Check if the same thing happens with Qt 4.1.4.

Just installed Qt 4.1.4 and the behaviour is the same. I would appreciate an answer to my first query: is it normal for the preview to be placed in the top-left corner of the screen without a title bar and is ESC the proper way of terminating it? This would narrow the field to just stacked widgets. Many thanks for any comments.

**jacek** · 28th September 2006, 22:09

Originally Posted by mikeh

I would appreciate an answer to my first query

As I already wrote, I don't think it's a correct behavior. IMO you should contact the Trolls as this looks like a bug.

**mikeh** · 2nd October 2006, 10:19

The source of this problem has now been identified. Firstly, the lack of response to ESC was my fault, I created a QWidget rather than a QDialog. As to the principal problem; the driver for the Matrox graphics card (millennium P650) I am using provides the option (in their words): 'save and restore the size and position of program windows each time you open and close program windows' and in my case this option was turned on; turning it off solves the problem.

The problem has been around for some time. With Qt3 its affect is to cause dialog windows to display at a larger size than expected when they are displayed for the first time. The behaviour reverts to normal after resizing. In the Qt4 Designer preview case the affect was more obvious and it seems to have screwed up the dialogs position as well as its size. I have never had any trouble from Microsoft apllications, or indeed any other than Qt applications.

Clearly, the Matrox driver must be up to tricks with the Win32 api and Qt is following a different practice in its window creation from that used in other applications. The simple solution for the developer is to turn the option off.

I should perhaps mention that the problem was still present using the latest Matrox driver P650 1.11.0.114 and Qt4.1.4.