我一直试图通过调用我的类的toJson函数来返回Map，但是我得到了NoSuchMethodError：Class'_InternalLinkedHashMap'没有实例方法'toJson'。所以我假设这不正确。 examples只包含可以转换为单个值的单个值，但不包含列表或映射的处理。那么在Dart中使用json_serializer处理将地图序列化为JSON的正确方法是什么？
我正在尝试序列化的类：
class StudentDailyReport {
final DocumentReference documentReference;
Student student;
// CheckIn
String attendanceStatus;
bool checkInChanged;
DateTime checkedInTime;
DateTime date;
// CheckOut
bool get checkedOut => this.attendanceStatus == AttendanceStatus.checkedOut;
bool checkOutChanged;
DateTime checkedOutTime;
// Mood
Mood mood;
bool moodHasChanged;
TextEditingController moodController;
// Supplies
Supplies supplies;
// Notes
Note note;
TextEditingController noteController;
bool noteChanged;
// Meals
Map<Meal, MealRecord> mealRecords;
bool mealsChanged;
// Health
Map<int, HealthEntry> healthEntries;
bool healthChanged;
//PottyLog
PottyLog pottyLog;
bool get pottyLogChanged => pottyLog.hasChanged;
ActivityLog activityLog;
bool get activityLogChanged => activityLog.hasChanged;
set activityLogChanged(bool value) =>
activityLog = activityLog.copyWith(hasChanged: value);
List<CaptionedPhoto> photos;
factory StudentDailyReport.initialFromStudent(Student student) {
return StudentDailyReport(
student: student,
moodController: TextEditingController(),
healthEntries: {0: HealthEntry.empty()},
supplies: Supplies(),
pottyLog: PottyLog.empty(),
activityLog: ActivityLog());
}
StudentDailyReport.fromDocument(DocumentSnapshot document)
: documentReference = document.reference {
Map json = document.data;
// Ensure that the student has been converted and inserted as a student object
// into the json before calling.
this.student = json['student'];
this.mood = json['mood'] != null ? Mood.fromJson(json['mood']) : Mood();
this.attendanceStatus = json['attendanceStatus'] ?? AttendanceStatus.none;
this.checkedInTime = json['checkedInTime'] != null
? (json['checkedInTime'] as Timestamp).toDate()
: null;
this.checkedOutTime = json['checkedOutTime'] != null
? (json['checkedOutTime'] as Timestamp).toDate()
: null;
this.supplies = json['supplies'] != null
? Supplies.fromJson(json['supplies'])
: Supplies();
this.note = json['note'] != null ? Note.fromJson(json['note']) : Note();
noteController = TextEditingController(text: note.comment);
this.mealRecords = MealRecord.mapFromJsonList(json['mealRecords']);
this.healthEntries = json['healthEntries'] != null
? (json['healthEntries'] as List)
.map((json) => HealthEntry.fromJson(json))
.toList()
.asMap()
: {0: HealthEntry.empty()};
this.pottyLog = json["pottyLog"] != null
? PottyLog.fromJson(json["pottyLog"])
: PottyLog();
this.activityLog = json["activityLog"] != null
? ActivityLog.fromJson(json["activityLog"])
: ActivityLog();
this.photos = json['photos'] != null
? (json['photos'] as List)
.map((photoJson) => CaptionedPhoto.fromJson(photoJson))
.toList()
: List<CaptionedPhoto>();
this.checkInChanged = false;
this.checkOutChanged = false;
this.healthChanged = false;
this.mealsChanged = false;
this.noteChanged = false;
this.moodHasChanged = false;
this.moodController = TextEditingController();
}
bool validateMeals() {
return mealRecords.values.any((mealRecord) => !mealRecord.isValid);
}
/// Used to indicate when changes need to be saved.
bool get hasUnsavedChanges {
bool result;
if (moodHasChanged == null ||
checkInChanged == null ||
supplies.suppliesHasChanged == null ||
checkOutChanged == null ||
noteChanged == null ||
checkOutChanged == null ||
mealsChanged == null ||
healthChanged == null ||
pottyLogChanged == null ||
activityLogChanged == null) {
debugPrint("One of these is null!");
}
try {
result = moodHasChanged ||
checkInChanged ||
supplies.suppliesHasChanged ||
checkOutChanged ||
noteChanged ||
checkOutChanged ||
mealsChanged ||
healthChanged ||
pottyLogChanged ||
activityLogChanged;
} on Exception {
return false;
}
return result;
}
StudentDailyReport({
this.documentReference,
this.student,
this.date,
// Mood
this.mood = const Mood(),
this.moodHasChanged = false,
this.moodController,
// Check In
this.attendanceStatus = AttendanceStatus.none,
this.checkInChanged = false,
this.checkedInTime,
//Check Out
this.checkOutChanged = false,
this.checkedOutTime,
// Supplies
this.supplies,
this.mealRecords = const {},
this.mealsChanged = false,
// Notes
this.noteController,
this.note = const Note.empty(),
this.noteChanged = false,
// Health
this.healthEntries,
this.healthChanged = false,
//PottyLog
this.pottyLog,
//ActivityLog
this.activityLog,
this.photos,
}) {
// assertions
if (attendanceStatus == AttendanceStatus.present) {
assert(checkedInTime != null);
}
if (attendanceStatus == AttendanceStatus.checkedOut) {
assert(checkedOutTime != null);
}
this.date ??= DateTime.now();
this.noteController = TextEditingController();
this.moodController = TextEditingController();
}
StudentDailyReport copyWith({
DocumentReference documentReference,
Mood mood,
bool moodChanged,
bool checkInChanged,
DateTime checkedInTime,
bool checkedOut,
DateTime checkedOutTime,
bool checkOutChanged,
TextEditingController moodController,
String attendanceStatus,
Note note,
Supplies supplies,
TextEditingController notesController,
bool notesChanged,
TextEditingController suppliesController,
bool suppliesChanged,
bool hasUnsavedChanges,
Map<Meal, MealRecord> mealRecords,
bool mealsChanged,
Map<int, HealthEntry> todaysHealthEntries,
bool healthChanged,
PottyLog pottyLog,
bool pottyLogChanged,
ActivityLog activityLog,
bool activityLogChanged,
List<CaptionedPhoto> photos,
DateTime date,
}) {
return StudentDailyReport(
documentReference: documentReference ?? this.documentReference,
student: this.student,
mood: mood ?? this.mood,
moodHasChanged: moodChanged ?? this.moodHasChanged,
checkInChanged: checkInChanged ?? this.checkInChanged,
attendanceStatus: attendanceStatus ?? this.attendanceStatus,
checkedInTime: (attendanceStatus == AttendanceStatus.present &&
checkedInTime == null)
? DateTime.now()
: checkedInTime ?? this.checkedInTime,
moodController: this.moodController,
note: note ?? this.note,
noteController: this.noteController,
noteChanged: noteChanged ?? this.noteChanged,
supplies: supplies ?? this.supplies,
checkOutChanged: checkOutChanged ?? this.checkOutChanged,
checkedOutTime: attendanceStatus == AttendanceStatus.present &&
checkedOutTime == null
? DateTime.now()
: this.checkedOutTime,
mealRecords: mealRecords ?? this.mealRecords,
mealsChanged: mealsChanged ?? this.mealsChanged,
healthEntries: todaysHealthEntries ?? this.healthEntries,
healthChanged: healthChanged ?? this.healthChanged,
pottyLog: () {
PottyLog newPottyLog = pottyLog ??= this.pottyLog;
if (pottyLogChanged == false) {
return newPottyLog.copyWith(hasChanged: false);
}
return newPottyLog;
}(),
activityLog: activityLog ?? this.activityLog,
photos: photos ?? this.photos,
date: date ?? this.date);
}
String get fullName => student.fullName;
Map<String, dynamic> toJson() {
Map<String, dynamic> data = {};
if (this.mood != null && this.mood.mood != "" && this.moodHasChanged) {
data["mood"] = this.mood.toJson();
}
// attendance
if (this.checkInChanged || this.checkOutChanged) {
data["attendanceStatus"] = this.attendanceStatus;
}
if (this.checkInChanged) {
assert(checkedInTime != null);
data['checkedInTime'] = Timestamp.fromDate(this.checkedInTime);
}
if (this.checkOutChanged) {
assert(checkedOutTime != null);
data['checkedOutTime'] = Timestamp.fromDate(this.checkedOutTime);
}
if (this.supplies.suppliesHasChanged) {
data["supplies"] = this.supplies.toJson();
}
if (this.mealsChanged) {
data['mealRecords'] = this
.mealRecords
.values
.map((mealRecord) => mealRecord.toJson())
.toList();
}
if (this.noteChanged) {
data['note'] = this.note.toJson();
}
data['student'] = this.student.documentReference;
if (healthChanged) {
data['healthEntries'] = healthEntries.values
.map((healthEntry) => healthEntry.toJson())
.toList();
}
if (this.pottyLogChanged) {
data['pottyLog'] = this.pottyLog.toJson();
}
if (this.activityLogChanged) {
data['activityLog'] = this.activityLog.toJson();
}
return data;
}
StudentDailyReport updateWith(DocumentSnapshot documentChange) {
Map json = documentChange.data;
return StudentDailyReport(
documentReference: documentChange.reference,
student: student,
mood: json['mood'] != null ? Mood.fromJson(json['mood']) : mood,
attendanceStatus: json['attendanceStatus'] ?? attendanceStatus,
checkedInTime:
(json['checkedInTime'] as Timestamp)?.toDate() ?? checkedInTime,
checkedOutTime:
(json['checkedOutTime'] as Timestamp)?.toDate() ?? checkedOutTime,
supplies: json['supplies'] != null
? Supplies.fromJson(json['supplies'])
: supplies,
note: json['note'] != null ? Note.fromJson(json['note']) : note,
mealRecords: MealRecord.mapFromJsonList(json['mealRecords']),
healthEntries: json['healthEntries'] != null
? (json['healthEntries'] as List)
.map((json) => HealthEntry.fromJson(json))
.toList()
.asMap()
: healthEntries,
pottyLog: json["pottyLog"] != null
? PottyLog.fromJson(json["pottyLog"])
: pottyLog,
activityLog: json["activityLog"] != null
? ActivityLog.fromJson(json["activityLog"])
: activityLog,
photos: json['photos'] != null
? (json['photos'] as List)
.map((json) => CaptionedPhoto.fromJson(json))
.toList()
: []);
}
@override
String toString() {
return "Report for $fullName";
}
}
目前我们不支持地图中的“复杂”键 - 就像Meal一样。
明星这个问题 - https://github.com/dart-lang/json_serializable/issues/396