Resize a QDockWidget ? (Width)

[Selven]

It's true, i don't define a layout for the widget... It's done now.

I have another problem, the first window has autofilbackground value to true, and a black background. So, the context menu of the QDockWidget is black, and I can't see the text... When I right click on the title bar of the QDockWidget, i have a context menu for set visible or not, the QDockWidget, (in clicking checkbox). This context menu have a background color black and a text color black too. So I can see it.
How can i modify this parameter ?

Thanks in advance for your help

[sedi]

I'm not sure if I understand you correctly. But it seems to me that you could use the Style Selectors to change the appearance of only those widgets you want to change - and not their children:
http://doc.qt.io/qt-4.8/http://qt-project.org/doc/qt-4.8/stylesheet-syntax.html