on function

void Function() on(
  1. EventTarget target,
  2. String event,
  3. void handler(
    1. Event event
    )
)

Attaches handler to event on target, returning a disposer that detaches it (handy for components that re-render and must avoid listener leaks).

Implementation

void Function() on(
  web.EventTarget target,
  String event,
  void Function(web.Event event) handler,
) {
  final js = handler.toJS;
  target.addEventListener(event, js);
  return () => target.removeEventListener(event, js);
}