Some questions about custom style

[charlse]

Hi guys:
I want to change the background-color of the label when the focus is on it, I used"

setStyleSheet( "QLabel:focus{ background-color: rgb( 255, 255, 255 ); }" );

setStyleSheet( "QLabel:focus{ background-color: rgb( 255, 255, 255 ); }" );

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to implement, Now I want to implement it through modifying the style, Where should I modify? drawComplexControl() ? drawControl() ? or other interfaces ? Thank you for suggestions.