I need help with Expanded Buttons

[thethinkingman]

I have been trying to make the group_button fill a row. I can do it without group_button but haven't worked out how to do it with it.

If I have 3 or more buttons I'd like there to be a space between the buttons.

What I am trying to achieve (as an example) is:
If I have 2 buttons, Jason and Samantha, when they are displayed in a Row that is 100% wide, Jason will take up 50% and Samantha the other 50%. If I had specified a space then there would be space between them.

Obviously I don't want to hard code button names.

Here is my code - that doesn't do what I want:

// Automatic FlutterFlow imports
import '/flutter_flow/flutter_flow_theme.dart';
import '/flutter_flow/flutter_flow_util.dart';
import '/custom_code/widgets/index.dart'; // Imports other custom widgets
import '/flutter_flow/custom_functions.dart'; // Imports custom functions
import 'package:flutter/material.dart';
// Begin custom widget code
// DO NOT REMOVE OR MODIFY THE CODE ABOVE!

import 'package:group_button/group_button.dart';

class GroupButtons extends StatefulWidget {
  const GroupButtons({
    super.key,
    this.width,
    this.height,
  });

  final double? width;
  final double? height;

  @override
  State<GroupButtons> createState() => _GroupButtonsState();
}

class _GroupButtonsState extends State<GroupButtons> {
  // Initialize the GroupButtonController to manage button selection
  final controller = GroupButtonController();

  @override
  Widget build(BuildContext context) {
    return Container(
      height: 50, // Set height of the container
      decoration: BoxDecoration(
        color: Color(0x00000000),
        borderRadius: BorderRadius.circular(6), // Border radius
        border: Border.all(
          color: Color(0x7f283043), // Border color
          width: 1, // Border width
        ),
      ),

      child: Row(
        mainAxisAlignment: MainAxisAlignment.spaceEvenly,
        children: [
          Expanded(
            child: GroupButton(
              controller: controller,
              isRadio: false,
              buttonIndexedBuilder: (selected, index, context) {
                return ElevatedButton(
                  onPressed: () => controller.selectIndex(1),
                  child: Text(
                    'Button ${index + 1}',
                    style: TextStyle(fontSize: 14),
                  ),
                );
              },
              onSelected: (String text, int index, bool isSelected) {
              },
              buttons: List.generate(3, (index) => 'Button ${index + 1}'),
            ),
          ),
        ],
      ),
    );
  }
}