Unable to change a Slate widget's style

I’m trying to make a slider widget with a slider handle that should be able to change its style depending on where the user released the button.

In Blueprints this is possible by using a Set slider style node, but I have not been able to replicate this in C++ code.

The slider derives from Slate’s SSlider and has functions like SetSliderBarColor() and SetSliderHandleColor(), but there is no SetStyle() or SetSliderStyle() which would take a FSliderStyle struct.

Is there a (relatively) simple way to achieve this?