问题
I am trying to find out the background color of a QWidget or QGLWidget so that I can use it with qglClearColor() to make the OpenGL part appear natively within the widget (without for example a black background).
I figured I could fetch backgroundRole() of my widget but I am having problems converting it to a QColor. There is QPalette::color(QColorRole) but it isn't static and I have no idea how I would have to create an instance of QPalette to do the transformation.
回答1:
Use QWidget::palette().color(QWidget::backgroundRole())to receive the color of the background color role for that widget. Obviously, this should also work with any class that inherits QWidget.
来源：https://stackoverflow.com/questions/15519749/how-to-get-widget-background-qcolor