小编Usa*_*rim的帖子

我用 freeze 创建了两个模型类。一个类内部有其他类的参数。当我尝试将数据发送到 firestore 时，问题开始了。出现以下错误。

E/flutter ( 6175): [ERROR:flutter/lib/ui/ui_dart_state.cc(209)] Unhandled Exception: Invalid argument: Instance of \'_$_Category\'\nE/flutter ( 6175): #0      convertPlatformException\npackage:cloud_firestore_platform_interface/\xe2\x80\xa6/utils/exception.dart:14\nE/flutter ( 6175): #1      MethodChannelDocumentReference.set\npackage:cloud_firestore_platform_interface/\xe2\x80\xa6/method_channel/method_channel_document_reference.dart:44\nE/flutter ( 6175): <asynchronous suspension>\nE/flutter ( 6175): #2      _JsonCollectionReference.add\npackage:cloud_firestore/src/collection_reference.dart:109\nE/flutter ( 6175): <asynchronous suspension>\nE/flutter ( 6175): #3      _WithConverterCollectionReference.add\npackage:cloud_firestore/src/collection_reference.dart:180\nE/flutter ( 6175): <asynchronous suspension>\nE/flutter ( 6175): #4      _HomeScreenState.product\npackage:mr_grocery/home/home_screen.dart:45\nE/flutter ( 6175): <asynchronous suspension>\n

模型类

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1. 产品（具有类别类参数）
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\n@freezed\nclass Product with _$Product {\n  const factory Product({\n    required int amount,\n    required List<Category> categories, // Category class generated by freezed\n …