ServiceList<Id, Data> constructor

ServiceList<Id, Data>(Service<Id, Data> service, { String idField = 'id', Equality<Data>? equality, })

Implementation

ServiceList(this.service, {this.idField = 'id', Equality<Data>? equality})
    : super([]) {
  _equality = equality;
  _equality ??= EqualityBy<Data, Id?>((map) {
    if (map is Map) {
      return map[idField] as Id?;
    } else {
      throw UnsupportedError(
          'ServiceList only knows how to find the id from a Map object. Provide a custom `Equality` in your call to the constructor.');
    }
  });
  // Index
  _subs.add(service.onIndexed.where(_notNull).listen((data) {
    this
      ..clear()
      ..addAll(data);
    _onChange.add(this);
  }));

  // Created
  _subs.add(service.onCreated.where(_notNull).listen((item) {
    add(item);
    _onChange.add(this);
  }));

  // Modified/Updated
  void handleModified(Data item) {
    var indices = <int>[];

    for (var i = 0; i < length; i++) {
      if (_equality!.equals(item, this[i])) indices.add(i);
    }

    if (indices.isNotEmpty) {
      for (var i in indices) {
        this[i] = item;
      }

      _onChange.add(this);
    }
  }

  _subs.addAll([
    service.onModified.where(_notNull).listen(handleModified),
    service.onUpdated.where(_notNull).listen(handleModified),
  ]);

  // Removed
  _subs.add(service.onRemoved.where(_notNull).listen((item) {
    removeWhere((x) => _equality!.equals(item, x));
    _onChange.add(this);
  }));
}