Download file with progress in Dart/Flutter using 'http' package

download_file.dart

import 'dart:async';
import 'dart:io';

import 'package:http/http.dart' as http;

///Returns the file as a stream of bytes
Future<Stream<List<int>>> downloadAsStream(String url) async {
  var result = await Client().send(
    Request(
      "get",
      Uri.parse(url),
    )..persistentConnection = false,
  );
  return result.stream;
}

///Returns the fully downloaded file
Future<List<int>> download(String url) async =>
    (await downloadAsStream(url)).fold([], (prev, element) => prev + element);