Flutter – How to use enum with const in a class

I am fairly new to Flutter and have made my first Reusable Widget. Below is a cleaner example on what I am trying to do.

My enum:

enum StreamBoxSize {

  final double borderRadius;
  const StreamBoxSize(this.borderRadius);

I am trying to give each enum value a default border radius value, so if I am choosing StreamBoxSize.small the border radius of my container is going to be 9.

My class looks like this:

class StreamBox extends StatelessWidget {
  const StreamBox({
    this.size = StreamBoxSize.large,
  final StreamBoxSize size;

  Widget build(BuildContext context) {
    return Container(
      decoration: BoxDecoration(
        color: Colors.white,
        borderRadius: BorderRadius.only(
          topLeft: Radius.circular(**borderRadius**),
          topRight: Radius.circular(**borderRadius**),
          bottomLeft: Radius.circular(**borderRadius**),
          bottomRight: Radius.circular(**borderRadius**),

I have marked in bold the value that of course doesnt work becaues my class dont know what borderRadius is. Any idea how to make it work? The value I want here is dynamic so everything will be 9 if I have choosen this:

StreamBox(size: StreamBoxSize.small),

>Solution :

Maybe you already tried and there’s something I’m missing, but why setting


for each side won’t work?

After all, StreamBoxSize.borderRadius is public and should be visible inside the build method…

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