Non client area painting with Qt

[rajendrant]

Dear Qt Developers/Experts

My goal is to draw tabbar in titlebar (only in Windows) similar to firefox/chrome.
I am using some DWM apis to achieve that as mentioned in http://msdn.microsoft.com/en-us/libr...=vs.85%29.aspx
Basically I make the entire area as nonclientarea and tabbar is drawn at the top automatically.

I know these DWM apis only work with Windows Aero enabled, and I am fine with tabbar not shown in titlebar with DWM disabled.

I am facing two issues.
1. When the application is maximized, part of the left, top window portion gets clipped. See the attached image.
2. If I enable 'Auto hide taskbar' property in Windows, I would expect the taskbar to popup when mouse is moved down near the taskbar with application maximized. That is not happening as well.

I have attached a sample project that creates the issue.
Can somebody help with this.
Any suggestions are welcome.

I can perfectly solve issue (1) with setContentsMargins() if I know the exact amount of pixels that are being clipped.

Thanks
Rajendran