background
Fills shape's outline with brush under the component's content.
An opaque component, such as a custom JPanel-based Decoratable under most looks and feels, fills its background over the brush, so declare opaque(false) on such a component for the fill to show. A Row, Column and Box are transparent unless set opaque. An outline other than RectangleShape is filled with an antialiased edge, as AndroidX's background fills it.
Return
this chain with the background declared on it.
Parameters
the fill, resolved against the decorated box.
the outline to fill; the whole decorated box by default.
the fraction of the brush's opacity to fill with; 1 by default. A value above 1 fills as 1, and one below 0 or NaN as 0.
Fills shape's outline with color under the component's content; the solid-color overload of background.
shape has no default here: the background taking a Color alone writes the Swing property, which is the one a look and feel honors, and a call naming only a color keeps meaning that one wherever both are imported.
Return
this chain with the background declared on it.
Parameters
the fill.
the outline to fill; RectangleShape for the whole decorated box.