This is the source code of the Flutter Challenges series post: https://fun4code.com/10flutterchallanges-part1/

candy_cane_progress_bar.dart

class CandyCaneProgressBar extends StatelessWidget {
  const CandyCaneProgressBar({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Stack(
      children: <Widget>[
        Container(
          width: MediaQuery.of(context).size.width,
          height: 20,
          decoration: BoxDecoration(
            border: Border.all(
              color: Colors.grey.shade200,
            ),
            color: Colors.white70,
          ),
        ),
        Container(
          width: MediaQuery.of(context).size.width - 100,
          height: 20,
          decoration: const BoxDecoration(
            gradient: LinearGradient(
              begin: Alignment(-0.75, -1.1),
              end: Alignment(-0.6, 0),
              stops: [0.0, 0.5, 0.5, 1],
              colors: [
                Colors.red,
                Colors.red,
                Colors.white,
                Colors.white,
              ],
              tileMode: TileMode.mirror,
            ),
          ),
        ),
        const Positioned.fill(
          child: Align(
            alignment: Alignment.center,
            child: Text(
              '200/1000',
              style: TextStyle(
                color: Colors.black,
                fontSize: 10,
                fontFamily: 'RetroGaming',
                fontWeight: FontWeight.bold,
              ),
            ),
          ),
        ),
      ],
    );
  }
}

custom_progress_bar.dart

class CustomProgressBar extends StatelessWidget {
  const CustomProgressBar({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Stack(
      children: <Widget>[
        SizedBox(
          width: MediaQuery.of(context).size.width,
          height: 20,
          child: const LinearProgressIndicator(
            backgroundColor: Color(0xff323232),
            valueColor: AlwaysStoppedAnimation<Color>(
              Color(0xFF21bf73),
            ),
            value: 0.5,
          ),
        ),
        const Positioned.fill(
          child: Align(
            alignment: Alignment.center,
            child: Text(
              '200/1000',
              style: TextStyle(
                color: Colors.white,
                fontSize: 10,
                fontFamily: 'RetroGaming',
                fontWeight: FontWeight.bold,
              ),
            ),
          ),
        )
      ],
    );
  }
}

main.dart

import 'package:flutter/material.dart';
import 'package:samples/progress_bar/progress_bar.dart';

void main() => runApp(const MyApp());

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      home: Scaffold(
        body: SafeArea(
          child: CandyCaneProgressBar(),
        ),
      ),
    );
  }
}