Issue
I have a class with a Map attribute, but it seems it doesn’t store this attribute. All other attributes are well stored:
@JsonSerializable()
@Entity()
class PossessionStats {
@JsonKey(defaultValue: 0)
int id;
String cardUuid;
int total;
Map<String, int>? totalByVersion;
CardPossessionStats({
this.id = 0,
required this.cardUuid,
this.total = 0,
this.totalByVersion,
});
}
When I save one:
stats = PossessionStats(cardUuid: card.uuid);
if (stats.totalByVersion == null) {
stats.totalByVersion = Map();
}
stats.totalByVersion!
.update(version, (value) => quantity, ifAbsent: () => quantity);
stats.total = stats.totalByVersion!.values
.fold(0, (previousValue, element) => previousValue + element);
box.put(stats);
When I get the results (after a refresh), I can see total
is correct but totalByVersion
is still empty.
Thanks!
Solution
For an unsupported type, you’ll need to add a "converter", as described by the docs (Custom types). You can adapt the docs to your code, for example using json
as the storage format:
@JsonSerializable()
@Entity()
class PossessionStats {
@JsonKey(defaultValue: 0)
int id;
String cardUuid;
int total;
Map<String, int>? totalByVersion;
String? get dbTotalByVersion =>
totalByVersion == null ? null : json.encode(totalByVersion);
set dbTotalByVersion(String? value) {
if (value == null) {
totalByVersion = null;
} else {
totalByVersion = Map.from(
json.decode(value).map((k, v) => MapEntry(k as String, v as int)));
}
}
}
Answered By – vaind
Answer Checked By – Gilberto Lyons (FlutterFixes Admin)