Is Filled controls whether a shape is filled in or if it is drawn using stroke - another word for outline. By default this is true, but it can be unchecked to make a shape draw its outline.
ColoredCircle toggling its Is Filled property
Stroke Width
Stroke Width controls the thickness of the stroke (outline). Increasing the value makes the stroke thicker.
Stroke Width controls the thickness of the outline
Stroke, Gradient, and Dropshadow
If a Skia standard element has its Is Filled unchecked, this affects the rendering of gradients and dropshadows.
Gradients only fill the solid parts of a shape, so if a shape has Is Filled set to false, the hollow center of the shape does not show gradient color.
Toggling Is Filled affects the gradient rendering at the center of the shape
Dropshadows respect the opaque part of the shape, so changing Is Filled also affects the dropshadow.
Changing a ColoredCircle's Is Filled to false results in the dropshadow having a hollow center
