downloadFile function

Implementation

Future<String> downloadFile(String uri, String file) {
  Completer<String> c = new Completer<String>();
  new HttpClient().getUrl(Uri.parse(uri))
    .then((HttpClientRequest request) => request.close())
    .then((HttpClientResponse response) {
      response.pipe(new File(file).openWrite()).then((a) {
        c.complete(file);
      });
    });
  return c.future;
}