paint method
Draw itself and its children, according to the calculated
box.offset
Implementation
@override
void paint(Context context) {
super.paint(context);
if (drawBorder) {
_paintShape(context);
context.canvas
..setLineWidth(borderWidth)
..setLineJoin(PdfLineJoin.round)
..setStrokeColor(borderColor ?? color)
..strokePath(close: true);
}
}