once method

void once(
  1. String event,
  2. EventHandler handler
)
inherited

This function binds the handler as a listener to the first occurrence of the event. When handler is called once, it is removed.

Implementation

void once(String event, EventHandler handler) {
  this._eventsOnce.putIfAbsent(event, () => <EventHandler>[]);
  this._eventsOnce[event]!.add(handler);
}