JSON serialize Map<String, bool>

main.dart

void main() {
  // サンプルデータ
  Map<String, bool> members = Map<String, bool>()
    ..putIfAbsent("userID1", () => true)
    ..putIfAbsent("userID2", () => true);
  print(members);

  var transMember = members.entries.map((member) {
    return <String, dynamic>{member.key: member.value};
  });
  print(transMember);
}