main.dart

import 'dart:math';
import 'dart:ui';

import 'package:flutter/material.dart';

final _random = Random();

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

class BackdropFilterDemo extends StatelessWidget {
  const BackdropFilterDemo({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        backgroundColor: Colors.black,
        body: Stack(
          children: [
            ListView.separated(
              separatorBuilder: (_, __) => const SizedBox(height: 8),
              itemBuilder: (context, index) => BlurEffect(
                child: Container(
                  height: 50,
                  color: Colors.primaries[_random.nextInt(17)].shade300,
                  child: Center(
                    child: Text(index.toString()),
                  ),
                ),
              ),
              itemCount: 200,
            ),
            Positioned.fill(
              bottom: null,
              child: BlurEffect(
                child: Padding(
                  padding: EdgeInsets.only(
                    top: MediaQuery.of(context).viewPadding.top,
                  ),
                  child: const SizedBox(height: 45),
                ),
              ),
            ),
            Positioned.fill(
              top: null,
              child: BlurEffect(
                child: Padding(
                  padding: EdgeInsets.only(
                    top: MediaQuery.of(context).viewPadding.bottom,
                  ),
                  child: const SizedBox(height: 50),
                ),
              ),
            ),
          ],
        ),
      ),
    );
  }
}

class BlurEffect extends StatelessWidget {
  final Widget child;

  const BlurEffect({
    required this.child,
    Key? key,
  }) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return ClipRect(
      child: BackdropFilter(
        filter: ImageFilter.blur(
          sigmaX: 28,
          sigmaY: 28,
          tileMode: TileMode.mirror,
        ),
        child: DecoratedBox(
          decoration: BoxDecoration(color: Colors.black.withOpacity(.65)),
          child: child,
        ),
      ),
    );
  }
}