Overwriting custom widget stylesheet from mainWindow

[pan]

Ok. Good to know the limitation. Working at runtime is a good enough solution.

I had been looking at this: QDesignerFormWindowInterface

But still wasn't able to access the main window.
Thanks for replying so quickly.

[high_flyer]

I had been looking at this: QDesignerFormWindowInterface

But still wasn't able to access the main window.

Heh, you are one step ahead of me, the trolls have added so much in last few Qt releases, that I have trouble to keep up, speically with such not very often used classes.
From a brief look in to QDesignerFormWindowInterface, I think that just might be what you are looking for.
Have a look at QDesignerFormEditorInterface::formWindowManager (), and then in QDesignerFormWindowManagerInterface.
I am almost certain that this will allow you to get the form styleSheet on which your custom widget is dropped.

[pan]

I finally got it working:

form = QDesignerFormWindowInterface::findFormWindow(widget);
form->mainContainer()->styleSheet();

form = QDesignerFormWindowInterface::findFormWindow(widget);
form->mainContainer()->styleSheet();

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This works for the designer.