How do I create an anonymous JavaScript function/callback with Dart's JS interop?

Vote count:

0

I am using Dart and its JS interop. I need to convert the following JavaScript code to Dart:

ID3.loadTags("filename.mp3", function() {
  var tags = ID3.getAllTags("filename.mp3");
  if (tags.artist)
    artist.textContent = tags.artist;
  if (tags.title)
    track.textContent = tags.title;
}, {
  dataReader: FileAPIReader(file)
});

Note the anonymous callback as the second parameter to loadTags. How do I create that with Dart and the dart:js library?

The closest I got was creating a named function with:

  js.context['loadTagsCallback'] = () {
    var tags = ID3.callMethod('getAllTags', ["filename.mp3"]);
    if (tags.artist != null) {
      artist.text = tags.artist;
    }
    if (tags.title != null) {
      track.text = tags.title;
    }
  };

And then using this code:

ID3.callMethod('loadTags', ["filename.mp3", js.context['loadTagsCallback'],
                            new js.JsObject.jsify({'dataReader': id3FileReader})
                           ]);

However, I don't want to create the named function. Any ideas or tips?

asked 21 secs ago

Seth Ladd

12.3k