unregister method

void unregister(
  1. Object eventName, [
  2. VoidValueCallback? f
])

Implementation

void unregister(Object eventName, [VoidValueCallback? f]) {
  var list = _eMap[eventName];
  if (list == null) return;
  if (f == null) {
    _eMap[eventName] = null;
  } else {
    list.remove(f);
  }
}