problem in Tab background

In my QT application,i set a background color for main widget.And when i am running the application in KUBUNTU,backg开发者_JAVA百科round of tab which i am using in my application is the same of main window,but when i run the application in windows,the tab's background becomes white and cant display anything on tab area.

Can anyone tell me a solution??

Thank you.

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There is a small problem with it. I will correct it and paste it at Pastebin soon.