# simpleImageRepository method Null safety

1. @override

SimpleImageRepository? simpleImageRepository(

1. String? appId

)
override

## Implementation

    @override
    SimpleImageRepository? simpleImageRepository(String? appId) {
      if ((appId != null) && (_simpleImageRepository[appId] == null)) {
        _simpleImageRepository[appId] = SimpleImageCache(SimpleImageFirestore(
            () => appRepository()!.getSubCollection(appId, 'simpleimage'),
            appId));
      }
      return _simpleImageRepository[appId];
    }