lineBorder
Sets a line border in color, thickness thick. The border is rebuilt only when color or thickness changes, so a chain that recomposes often leaves the component's border alone. See border for the one border a chain declares.
Return
this chain with the line border declared on it.
Parameters
color
the color of the line drawn just inside the component's edges.
thickness
how wide the line is on each side, 1 by default.