How to use a javascript library in dart?

Question

I was wondering how to use a javascript library in dart ? There are several examples in the web but either they do not work, or they are super verbose, and they are all at least 2 years old.

I want to use the D3 library in my case

Thanks

Answer 1

The likely simplest method of using javascript in dart is to use immediately is the dart:js library, where you can use context.callMethod to call methods in javascript.

Ex.

import 'dart:js';

main() => context.callMethod('alert', ['Hello from Dart!']);//'alert' is the function name, the second parameter is a `List` of arguments passed to the function.

---

Alternatively, you can use package:js, which should usually be used and provides higher level functionality, but it may be harder to start using because the documentation is a bit spotty. This library uses annotations with the external keyword to handle dart-JS interop.

Ex.

@JS()
library stringify;

import 'package:js/js.dart';

// Calls invoke JavaScript `JSON.stringify(obj)`.
@JS('JSON.stringify')
external String stringify(Object obj);

With this, you can then call stringify elsewhere and static analysis will be able to better pick up on type errors because you can explicitly define parameter and return types.