addEventListener method

  1. @mustCallSuper
void addEventListener(
  1. String eventType,
  2. EventHandler eventHandler, {
  3. EventListenerOptions? addEventListenerOptions,
})

Implementation

@mustCallSuper
void addEventListener(String eventType, EventHandler eventHandler, {EventListenerOptions? addEventListenerOptions}) {
  if (_disposed) return;
  bool capture = false;
  if (addEventListenerOptions != null)
    capture = addEventListenerOptions.capture;
  List<EventHandler>? existHandler = capture ? _eventCaptureHandlers[eventType] : _eventHandlers[eventType];
  if (existHandler == null) {
    if (capture)
      _eventCaptureHandlers[eventType] = existHandler = [];
    else
      _eventHandlers[eventType] = existHandler = [];
  }
  existHandler.add(eventHandler);
}