Flutter 无法将参数类型“GeneratedIntColumn”分配给参数类型“int”：摩尔颤振

当连接两个表时，我试图设置一个外键与moorflatter的关系，我在VS代码中得到下面的错误

无法将参数类型“GeneratedIntColumn”分配给参数类型“int”

起初我认为这是因为我使用了一个自动递增字段作为外键，但现在我不太确定，因为当我更改代码时仍然会出现错误

这是我的密码。比较时join语句发生错误；tasks.id.equalscategories.taskId

import 'package:moor/moor.dart';
import 'package:moor_flutter/moor_flutter.dart';

part 'moor_database.g.dart';

@DataClassName("Category")
class Categories extends Table {
  IntColumn get id => integer().autoIncrement()();
  IntColumn get taskId =>
      integer().nullable().customConstraint('NULL REFERENCES tasks(id)')();
  TextColumn get name => text().withLength(min: 1, max: 100)();
  TextColumn get icon => text()();
  TextColumn get color => text()();
}

class Tasks extends Table {
  IntColumn get id => integer().autoIncrement()();
  TextColumn get name => text().withLength(min: 1, max: 200)();
  BoolColumn get completed => boolean().withDefault(Constant(false))();
}

@UseMoor(tables: [Categories, Tasks], daos: [CategoryDao])
class AppDatabase extends _$AppDatabase {
  AppDatabase()
      : super((FlutterQueryExecutor.inDatabaseFolder(
          path: 'todo.sqlite',
          logStatements: true,
        )));

  @override
  int get schemaVersion => 1;

  @override
  MigrationStrategy get migration =>
      MigrationStrategy(beforeOpen: (details) async {
        await customStatement('PRAGMA foreign_keys = ON');
      });
}

class CategoryWithTask {
  final Category category;
  final Task task;

  CategoryWithTask({@required this.category, @required this.task});
}

@UseDao(tables: [Categories, Tasks])
class CategoryDao extends DatabaseAccessor<AppDatabase>
    with _$CategoryDaoMixin {
  final AppDatabase db;

  CategoryDao(this.db) : super(db);
  Stream<List<CategoryWithTask>> watchAllCategories() {
    return (select(categories)
          ..orderBy(([
            (c) => OrderingTerm(expression: c.name),
          ])))
        .join([leftOuterJoin(tasks, tasks.id.equals(categories.taskId))])
        .watch()
        .map((rows) => rows.map((row) {
              return CategoryWithTask(
                  category: row.readTable(categories),
                  task: row.readTable(tasks));
            }));
  }
}

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通过查看来自的代码示例，我意识到了我的错误

而不是tasks.id.equalscategories.taskId

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如果要从类别表中检索任务表中的名称并将其显示在列表中，则联接中的表达式应为tasks.id.equalsExpcategories.taskId

Hi。你打算怎么办？