Flutter WEB download option

Question

I am making flutter web app that should generate a file from user data. And have the option to download the output file.

But I can not find any options/packages whic

Answer 1

you can use package url_launcher with url_launcher_web

then you can do:

launch("data:application/octet-stream;base64,${base64Encode(yourFileBytes)}")

EDIT: you don't need a plugin if you do this

download.dart:

import 'dart:convert';
// ignore: avoid_web_libraries_in_flutter
import 'dart:html';

void download(
  List bytes, {
  String downloadName,
}) {
  // Encode our file in base64
  final _base64 = base64Encode(bytes);
  // Create the link with the file
  final anchor =
      AnchorElement(href: 'data:application/octet-stream;base64,$_base64')
        ..target = 'blank';
  // add the name
  if (downloadName != null) {
    anchor.download = downloadName;
  }
  // trigger download
  document.body.append(anchor);
  anchor.click();
  anchor.remove();
  return;
}

empty_download.dart:

void download(
  List bytes, {
  String downloadName,
}) {
  print('I do nothing');
}

import and use:

import 'empty_download.dart'
if (dart.library.html) 'download.dart';

void main () {
  download('I am a test file'.codeUnits, // takes bytes
      downloadName: 'test.txt');
}