onChange method

@mustCallSuper void onChange(StateChange<State> change)

Called whenever a change occurs with the given change. A change occurs when a new state is emitted. onChange is called before the state of the StateController is updated. onChange is a great spot to add logging/analytics for a specific StateController.

Note: super.onChange should always be called first.

@override
void onChange(StateChange change) {
  // Always call super.onChange with the current change
  super.onChange(change);

  // Custom onChange logic goes here
}

See also:

• ObserverController for observing StateController behavior globally.

Implementation

@mustCallSuper
void onChange(StateChange<State> change) {
  // ignore: invalid_use_of_protected_member
  Controller.observer.onChange(this, change);
}