layout method
layout API.
Implementation
@override
PwBox layout(Context context, BoxConstraints constraints) {
final PwBox box = child.layout(
context,
const BoxConstraints(),
);
final PwSize dest = PwSize(
constraints.hasBoundedWidth ? constraints.maxWidth : box.size.width,
constraints.hasBoundedHeight ? constraints.maxHeight : box.size.height,
);
return _FittedBox(constraints.constrain(dest), box, fit, alignment);
}