void uploadFile() async {

submitButton.attributes.addAll({'disabled': ''});
progress.value = 0;

FileList files = input.files;

if(files.isEmpty){
  _handleError("No file selected");
  //handle error, probably a banner
  return;
}

File file = files.item(0);

FileReader reader = new FileReader();
//reader.result
reader.onLoadEnd.listen((e) async {


  Map map = json.decode(reader.result);

  var combinations = map['combinations'];

  progress.max = combinations.length;

  int loopCount = 0;

  combinations.forEach((e) async {
    await _service.create(VJCombination.fromJSON(e)).then((_) {
      combinationCount++;
      progress.value ++;

      loopCount++;

      if(loopCount == combinations.length){
        submitButton.attributes.remove('disabled');
      }
    });

  });

  isLoadSuccessful = true;

});

reader.onError.listen((evt) => print(evt));

reader.readAsText(file);

progress.value = 10;

}

@ViewChild('progress')
ProgressElement progress;

@ViewChild('submit')
ButtonElement submitButton;