Flutter 颤振发布运行生成\运行程序生成失败

颤振版本：

flutter_macos_v1.9.1+hotfix.2-stable

Analyzer: 0.39.14 

在终端中创建新项目：

flutter create myapp

flutter pub get

[INFO] Generating build script...
[INFO] Generating build script completed, took 321ms

[INFO] Creating build script snapshot......
[INFO] Creating build script snapshot... completed, took 10.4s

[INFO] Initializing inputs
[INFO] Building new asset graph...
[INFO] Building new asset graph completed, took 698ms

[INFO] Checking for unexpected pre-existing outputs....
[INFO] Checking for unexpected pre-existing outputs. completed, took 2ms

[INFO] Running build...
[SEVERE] json_serializable:json_serializable on lib/user.dart:

Invalid argument(s): Path must be absolute : dart:core
[SEVERE] json_serializable:json_serializable on lib/main.dart:

Invalid argument(s): Path must be absolute : dart:core
[SEVERE] json_serializable:json_serializable on test/widget_test.dart:

Invalid argument(s): Path must be absolute : dart:core
[INFO] Running build completed, took 1.5s

[INFO] Caching finalized dependency graph...
[INFO] Caching finalized dependency graph completed, took 36ms

[SEVERE] Failed after 1.6s

打开vscode，编辑pubspec.yaml：

dependencies:
  json_annotation: ^3.0.0

dev_dependencies:
  build_runner: ^1.7.0
  json_serializable: ^3.2.2

在终端中获取包：

flutter create myapp

flutter pub get

[INFO] Generating build script...
[INFO] Generating build script completed, took 321ms

[INFO] Creating build script snapshot......
[INFO] Creating build script snapshot... completed, took 10.4s

[INFO] Initializing inputs
[INFO] Building new asset graph...
[INFO] Building new asset graph completed, took 698ms

[INFO] Checking for unexpected pre-existing outputs....
[INFO] Checking for unexpected pre-existing outputs. completed, took 2ms

[INFO] Running build...
[SEVERE] json_serializable:json_serializable on lib/user.dart:

Invalid argument(s): Path must be absolute : dart:core
[SEVERE] json_serializable:json_serializable on lib/main.dart:

Invalid argument(s): Path must be absolute : dart:core
[SEVERE] json_serializable:json_serializable on test/widget_test.dart:

Invalid argument(s): Path must be absolute : dart:core
[INFO] Running build completed, took 1.5s

[INFO] Caching finalized dependency graph...
[INFO] Caching finalized dependency graph completed, took 36ms

[SEVERE] Failed after 1.6s

新建

/lib/user.dart

并填充以下内容：

import 'package:json_annotation/json_annotation.dart';

part 'user.g.dart';

@JsonSerializable()
class User extends Object {
  @JsonKey(name: 'seed')
  String seed;

  @JsonKey(name: 'results')
  int results;

  @JsonKey(name: 'page')
  int page;

  @JsonKey(name: 'version')
  String version;

  User(
    this.seed,
    this.results,
    this.page,
    this.version,
  );

  factory User.fromJson(Map<String, dynamic> srcJson) =>
      _$UserFromJson(srcJson);

  Map<String, dynamic> toJson() => _$UserToJson(this);
}

为什么从来没有成功过

我也有同样的问题

已成功生成所有*.g.dart文件，包括： build_runner 0.9.2

json_可序列化0.5.8+1

---

json_注释0.2.9+1

看起来Analyzer正在破坏它，降级到

Analyzer:0.38.2

为我解决了它

---

来源：

在这种情况下可能不是这样，但是我的自动格式化程序删除了这一行，导致了类似的问题：

part 'my_class.g.dart';

---

一旦我添加了那一行并再次运行命令，它就工作得很好。

我也有同样的问题，所以我只是先在类中保存更改（在您的例子中是

User

class）。
然后我用以下方法重试：

flutter pub run build_runner build

试试这个

flutter pub get && flutter pub run build_runner build --delete-conflicting-outputs

---

在pubsec.yaml中添加依赖项，分析器：“0.39.14”

flutter clean
flutter pub cache repair
flutter pub run build_runner clean

然后跑,

flutter pub run build_runner build

---

在尝试了上述所有建议的漫长过程后，我使用了最新的build_runner和json_可序列化版本： 生成运行程序：^1.10.2 json_可序列化：^3.4.0 不确定最终的效果如何，但我的案例中的一个问题似乎是一个稍微过时的dart SDK，所以还有一件事需要注意

更新2020/8/24： 在版本中似乎破坏了build_runner或json_可序列化：

Analyzer: 0.39.16 

返回dart analyzer版本：

flutter_macos_v1.9.1+hotfix.2-stable

Analyzer: 0.39.14 

帮我修好了。

---

因此，0.39.16中出现了一些问题。

请确保类名与生成的文件名相同。例如：

部分“用户”.g.dart”

类用户{

---

}

我尝试了许多解决方案，但错误并没有消失<代码>颤振包pub run build_runner watch命令以无休止的日志运行

---

我删除了pubspec.lock并运行了

flatter-pub-get

，再次安装了dependency并运行了上述命令。此错误消失后。

请在

flatter packages pub run build\u runner build

命令之前为models类创建默认的空构造函数，描述您试图实现的目标，而不是只发布代码，这将有助于其他人理解问题。不要试图绕过stackoverflow限制DART 2.0存在某种错误，并显示相同的错误消息。他试图自动生成Json序列化，就像我一样，并且遇到了同样的错误。没有任何意义。以下是我们关注的内容：帮助您解决了这个问题吗？我也有同样的问题。我想不出来。@bradbury9自动json序列化/反序列化，请检查我的其他评论。使用Moor解决了这个问题，并且这个解决方案对我有效。谢谢您的回答！build_runner:^1.10.2需要Dart版本2.-10.0+，因此，我将版本更改为1.10.1，幸运的是它成功了。添加

flatter pub get

after

flatter pub run build_runner clean

，它为我成功了！