问颤振飞镖MissingPluginException

EN

Error: MissingPluginException(No implementation found for method getDatabasesPath on channel com.tekartik.sqflite)
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/errors.dart 266:49  throw_
packages/flutter/src/services/platform_channel.dart 294:7                                                                  _invokeMethod
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 45:50            <fn>
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/zone.dart 1653:54                                          runUnary
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/future_impl.dart 147:18                                    handleValue
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/future_impl.dart 766:44                                    handleValueCallback
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/future_impl.dart 795:13                                    _propagateToListeners
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/future_impl.dart 566:5                                     [_completeWithValue]
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/future_impl.dart 639:7                                     callback
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/schedule_microtask.dart 40:11                              _microtaskLoop
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/schedule_microtask.dart 49:5                               _startMicrotaskLoop
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 166:15           <fn>
Error: MissingPluginException(No implementation found for method openDatabase on channel com.tekartik.sqflite)
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/errors.dart 266:49  throw_
packages/flutter/src/services/platform_channel.dart 294:7                                                                  _invokeMethod
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 45:50            <fn>
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/zone.dart 1399:47                                          _rootRunUnary
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/zone.dart 1300:19                                          runUnary
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/future_impl.dart 147:18                                    handleValue
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/future_impl.dart 766:44                                    handleValueCallback
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/future_impl.dart 795:13                                    _propagateToListeners
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/future_impl.dart 566:5                                     [_completeWithValue]
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/future_impl.dart 639:7                                     <fn>
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/zone.dart 1391:13                                          _rootRun
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/zone.dart 1293:19                                          run
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/zone.dart 1225:23                                          callback
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/schedule_microtask.dart 40:11                              _microtaskLoop
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/schedule_microtask.dart 49:5                               _startMicrotaskLoop
C:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 166:15           <fn>
```'

import 'dart:async'; import 'package:flutter\_app/Book.dart'; import "package:sqflite/sqflite.dart"; import "package:path/path.dart";

class db\_helper { Database? conn;

Future<Database?> get dbConn async { if (conn == null) { conn = await connectDB(); }else{ return conn; } return conn; }

Future<Database?> connectDB() async { String path = join(await getDatabasesPath().toString(), "library.db"); var connection = openDatabase("library.db", version: 2, onCreate: createDB); return connection; }

FutureOr<void> createDB(Database db, int version) async { Database? conn = await this.dbConn; return await conn?.execute("create table books (id text not null unique, name text not null)"); }

Future<List<Book>> getBooks() async {

```javascript

booksList[i].id,

booksList[i].name

}

Future<void> addBook(Map<String, String> book) async { Database? conn = await this.dbConn; await conn?.insert("books", book); conn?.close(); } }

```javascript

name: flutter_app
description: A new Flutter application.

publish_to: 'none' # Remove this line if you wish to publish to pub.dev

version: 1.0.0+1

environment:
sdk: '\>=2.18.4 \<3.0.0'

dependencies:
flutter:
sdk: flutter
path: ^1.8.2
sqflite: ^2.2.0+3

cupertino_icons: ^1.0.2

dev_dependencies:
flutter_test:
sdk: flutter

flutter_lints: ^2.0.0

flutter:
uses-material-design: true