# Interface HomeStructureListener

public interface HomeStructureListener

Told when the home graph moves -- an accessory added, removed, renamed, moved between rooms, or its reachability changing.

Register with `SmartHome.addStructureListener(HomeStructureListener)`. Deliveries arrive on the EDT, so a listener may touch components directly.

This is about topology, not values. A light being switched on is not a structure change; subscribe to `Trait.ON_OFF` for that.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `void`
  `structureChanged(HomeStructureEvent event)`
  The home graph moved.

- ## Method Details

  - ### structureChanged

    void structureChanged(HomeStructureEvent event)

    The home graph moved. Re-fetch what the event says is stale.

    ###### Parameters

    - `event`: what changed, never `null`