fetch method
Implementation
@override
Future<Iterable<Conversation>> fetch({
int? limit,
int? skip,
}) async {
if (skip == null || limit == null) return [];
var ids = _conversationIds!.skip(skip).take(limit);
var futures = <Future<Conversation?>>[];
for (var id in ids) {
var future = _loadConversation(id);
futures.add(future);
}
List<Conversation?> conversations = await Future.wait(futures);
return conversations.whereType<Conversation>();
}