paint method
Paints this render object into the given context at offset.
Implementation
@override
void paint(PaintingContext context, Offset offset) {
_ensureStylesCached();
final int w = size!.width;
_paintBackground(context, offset.x.toInt(), offset.y.toInt(), w);
if (value != null) {
_paintDeterminate(context, offset.x.toInt(), offset.y.toInt(), w);
} else {
_paintIndeterminate(context, offset.x.toInt(), offset.y.toInt(), w);
}
}