我的json序列化有一些问题,我使用json_serializable: ^6.2.0,所以我的代码是:
shift.dart
import 'package:hive/hive.dart';
import 'package:json_annotation/json_annotation.dart';
part 'shift.g.dart';
@HiveType(typeId: 1)
@JsonSerializable()
class Shift extends HiveObject {
@HiveField(0)
final Dat
我想解析一个由数组组成的复杂JSON API,它显示了以下错误。API有天气的详细信息,我想在控制台中显示时间和波高。
错误
E/flutter ( 5675): [ERROR:flutter/lib/ui/ui_dart_state.cc(186)] Unhandled Exception: type '_InternalLinkedHashMap<String, dynamic>' is not a subtype of type 'List<dynamic>'
E/flutter ( 5675): #0 _JsonDem
我有一个想要保存到本地存储的对象,但是每当我将该对象写入存储时,我都会得到标题中显示的错误。
这是完整的堆栈跟踪
[VERBOSE-2:ui_dart_state.cc(198)] Unhandled Exception: type '_InternalLinkedHashMap<String, dynamic>' is not a subtype of type 'Map<String, double>' in type cast
#0 new Product.fromJson (package:app/src/objects
我有两个模型:book和review。
在book.dart中,我有一个字段来列出与这本书相关的评论(在review.dart中定义)。
class Book {
final String id;
final String bookid;
final String title;
final String author;
final DateTime purchDate;
final String intro;
final List<Review> reviews;
Book(this.id, this.bookid, this.title, thi
我有一个名为ShoppingListProduct的对象,它有一个id (字符串)、一个滴答(布尔),还有一个产品(产品)。
所以,当我想从json读ShoppingListProduct的时候。
class ShoppingListProduct extends Equatable {
ShoppingListProduct({
required this.ID,
required this.product,
required this.ticked,
});
final int ID;
final Product product;
late
import 'dart:convert';
import 'package:flutter/foundation.dart';
import 'package:http/http.dart' as http;
import './cart.dart';
class OrderItem {
final String id;
final double amount;
final List<CartItem> products;
final DateTime dateTime;
OrderItem
我有这样的错误,type List<dynamic> is not a subtype of type Map<String, dynamic>,我已经搜索了很多问题,但仍然无法理解错误的目的。这是我的api代码
import 'dart:convert';
import 'package:learn_how_to_fetch/announcement.dart';
import 'package:requests/requests.dart';
Future<Announcement> fetchAnno
据我所知,对于静态类型,数据类型在编译时已知,对于动态类型,数据类型在运行时已知/评估。
Dart文档()说dart是一种静态类型的语言-
Q. Is Dart a statically typed language?
Yes, Dart 2 is statically typed. For more information, read about Dart’s type system.
With its combination of static and runtime checks, Dart has a sound type system, which guarantees that
我试图在我的颤振应用程序中显示来自json的数据,我的错误:
[ERROR:flutter/lib/ui/ui_dart_state.cc(198)] Unhandled Exception: type '_InternalLinkedHashMap<String, dynamic>' is not a subtype of type 'List<dynamic>' in type cast
我的方法:
List _loadedAkhbar = [];
Future<void> _fetchData() async {
每当试图调用未来的数据并尝试转换为List时,它都会返回错误
类型“未来”不是“列表”的子类型
尝试过类型转换,但没有帮助。
论HomePage.dart
final getPost = NetworkFile().getPosts();
List posts;
void getPostsList() {
setState(() {
var res = getPost;
posts = res as List<dynamic>;
print(posts);
});
}
论Network.dart
class