slider.knob < layer>

The knob of the slider. By default, it's made circular using borderRadius and has a little bit of a drop shadow applied to it.
译：滑块的旋钮。默认情况下，它是由圆形使用borderRadius并应用了一点点阴影。

# Create a SliderComponent  
slider = new SliderComponent
slider.center()

# Customize the appearance 
slider.knob.shadowY = 2
slider.knob.shadowBlur = 4
slider.knob.borderRadius = 6

The knob is a draggable layer, with momentum enabled.
译：旋钮可拖动的层，使动量启用。

# Disable momentum 
slider.knob.draggable.momentum = false