How to get widget background QColor
qt, qwidget
Solution
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.
Problem
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.