copy method
Copy particular properties from another StateX
Implementation
@mustCallSuper
void copy([StateX? state]) {
//
if (state == null) {
return;
}
// Copy over certain properties
_recException = state._recException;
_ranFuture = state._ranFuture;
_listenersBefore.addAll(state._listenersBefore);
_listenersAfter.addAll(state._listenersAfter);
// Important!? Other controllers may have been added!
_mapControllers.addAll(state._mapControllers);
}