registerCustomerJourneyChangedHandler

Register a callback that will be made any time there's a change to the Journey State for the user. Note that Nami fetches journey state at the start of each session and this is the most likely time to see a change.

@objc static func registerJourneyStateChangedHandler( _ changeHandler: NamiCustomerJourneyChangeHandler? )

public typealias NamiCustomerJourneyChangeHandler = (_ newCustomerJourneyState: CustomerJourneyState) -> ()

NamiCustomerManager.registerCustomerJourneyChangedListener { journeyState -> 
  // code to process state change
}

NamiCustomerManager.registerCustomerJourneyChangedListener((journeyState) -> {
  // code to process state change
}

const onCustomerJourneyStateChanged = (event) => {
  // react to journey state change
}

useEffect(() => {
  ...
  if (
    eventEmitter?._subscriber?._subscriptionsForType?.CustomerJourneyStateChanged == null
  ) {
    eventEmitter.addListener('CustomerJourneyStateChanged', onCustomerJourneyStateChanged);
  }
}, []);