How to the background of QPrintPreviewWidget ?

[Heterodontus]

Hi,
I met a problem with QPrintPreviewWidget ,which is that I can not change the background of it by QStyle Sheet. Can somebody give me some advice?
Thanks!

[wysota]

What exactly did you try and how does the result differ from what you had expected?

[Heterodontus]

Hi,
Thanks for your answer.

"QPrintPreviewWidget{
background: #1E1E1E;
}"

I added abvoe lines to my StyleSheet file(*.qss).But it dose not work.Because the background of the QPrintPreviewWidget I created in my project is still default,which is different from the color :#1E1E1E.