Http client stream listen only called when the file is downloading

[kjawadDeveloper]

I want to listen to the progress during the image download. It works well in android and ios but in the web I only get this listen to callback when the image is downloaded.

    var _response = await Client().send(Request("GET",  
    Uri.parse("https://upload.wikimedia.org/wikipedia/commons/f/ff/Pizigani_1367_Chart_10MB.jpg")));

    _total = _response.contentLength;


      _response.stream.listen((value) {
            print("received: ${value.length}");
            _bytes.addAll(value);
            _received += value.length;

        setState(() {

            });
      }).onDone(() {
          setState(() {
            // _image = Uint8List.fromList(_bytes);
          });
      });```

[ditman]

It seems the browser_client.dart is only listening to the onLoad event of a request, instead of its progress events:

• https://github.com/dart-lang/http/blob/master/lib/src/browser_client.dart#L55-L65

This is probably why when send is used in the web, the response goes straight from 0 to 100% in only one progress event.

[natebosch]

The browser client does not support streaming because it uses XmlHttpRequest so no response object becomes available until the entire response is read. No plans in the short term, but we might investigate using fetch to support streaming. #595