2

双用户，

我在 iOS 中成功使用带有 sqflite 的数据库运行，

但是我在android中遇到了问题..

DBHelper 代码：

import 'package:path_provider/path_provider.dart';
import 'package:sqflite/sqflite.dart';
import 'package:socialapp/model/todo.dart';
import 'dart:async';
import 'dart:io';
import 'package:path/path.dart';



final String tableName = 'person';

class DBHelper{
  DBHelper._();
  static final DBHelper _db = DBHelper._();
  factory DBHelper() => _db;

  //해당 변수에 데이터베이스 정보 저장
  static Database _database;

  Future<Database> get database async{
    if(_database == null){
      print('데이터베이스 없음 , 초기화 시작');
      _database = await initDB();
      return _database;}else {
      print('이미 데이터베이스가 존재');
      return _database;
    }
  }


  initDB() async{
//    Directory documentsDirectory = await getApplicationDocumentsDirectory();
    String path = join('/Users/landwhale', 'Person_Pro_file.db');
    print('초기화중');
    print(path);
    return await openDatabase(
      path,
      version: 1,
      onOpen: (db) {},
      onCreate: (Database db, int version) async{
        await db.execute('''
        CREATE TABLE $tableName(
        id INTEGER PRIMARY KEY,
        name TEXT,
        intro TEXT,
        age TEXT) ''');
      },
    );
  }


  createData(Todo todo)async{
    print('데이터베이스 생성중..');
    final db = await database;
    print('데이터베이스 추가중 ...');
    var res = await db.insert(tableName, todo.toJson());
    print('데이터베이스 추가완료');
    return res;
  }

  //read
  getTodo(int id) async{
    final db = await database;
    var res = await db.query(tableName, where: 'id = ?', whereArgs: [id]);
    return res.isNotEmpty ? Todo.fromJson(res.first) : Null;
  }

//  getAllTodos() async{
//    final db = await database;
//    var res = await db.query(tableNam
//  }
  updateTodo(Todo todo) async{
    final db = await database;
    var res = await db.update(tableName, todo.toJson(),
        where: 'id =?' , whereArgs: [todo.id]);
    return res;
  }

  //Delete
  deleteTodo(int id) async{
    final db = await database;
    db.delete(tableName, where: 'id =?', whereArgs: [id]);
  }

  deleteAllTodos() async{
    final db =await database;
    db.rawDelete("Delete * from $tableName");
  }
}

待办事项代码：



class Todo {
  int id;
  String name;
  String intro;
  String age;

  Todo({
    this.id,
    this.name,
    this.intro,
    this.age,});

  factory Todo.fromJson(Map<String, dynamic> json) => Todo(
    id: json["id"],
    intro: json["intro"],
    name: json["name"],
    age: json["age"],
  );

  Map<String, dynamic> toJson() =>
      {
        "id" :id,
        "name": name,
        "age": age,
        "intro" : intro,
      };

}

错误 ：

데이터베이스 생성중..
I/flutter ( 2952): 데이터베이스 없음 , 초기화 시작
I/flutter ( 2952): 초기화중
I/flutter ( 2952): /Users/landwhale/Person_Pro_file.db
E/flutter ( 2952): [ERROR:flutter/lib/ui/ui_dart_state.cc(148)] Unhandled Exception: DatabaseException(open_failed /Users/landwhale/Person_Pro_file.db)
E/flutter ( 2952): #0      wrapDatabaseException (package:sqflite/src/exception_impl.dart:11:7)
E/flutter ( 2952): <asynchronous suspension>
E/flutter ( 2952): #1      SqfliteDatabaseFactoryImpl.wrapDatabaseException (package:sqflite/src/factory_impl.dart:29:7)
E/flutter ( 2952): #2      SqfliteDatabaseMixin.safeInvokeMethod (package:sqflite/src/database_mixin.dart:184:15)
E/flutter ( 2952): #3      SqfliteDatabaseMixin.openDatabase (package:sqflite/src/database_mixin.dart:519:15)
E/flutter ( 2952): <asynchronous suspension>
E/flutter ( 2952): #4      SqfliteDatabaseMixin.doOpen (package:sqflite/src/database_mixin.dart:612:28)
E/flutter ( 2952): <asynchronous suspension>
E/flutter ( 2952): #5      SqfliteDatabaseOpenHelper.openDatabase (package:sqflite/src/database.dart:32:22)
E/flutter ( 2952): <asynchronous suspension>
E/flutter ( 2952): #6      SqfliteDatabaseFactoryMixin.openDatabase.<anonymous closure> (package:sqflite/src/factory_mixin.dart:100:43)
E/flutter ( 2952): <asynchronous suspension>
E/flutter ( 2952): #7      ReentrantLock.synchronized.<anonymous closure>.<anonymous closure> (package:synchronized/src/reentrant_lock.dart:33:24)
E/flutter ( 2952): #8      _rootRun (dart:async/zone.dart:1124:13)
E/flutter ( 2952): #9      _CustomZone.run (dart:async/zone.dart:1021:19)
E/flutter ( 2952): #10     _runZoned (dart:async/zone.dart:1516:10)
E/flutter ( 2952): #11     runZoned (dart:async/zone.dart:1463:12)
E/flutter ( 2952): #12     ReentrantLock.synchronized.<anonymous closure> (package:synchronized/src/reentrant_lock.dart:32:24)
E/flutter ( 2952): <asynchronous suspension>
E/flutter ( 2952): #13     BasicLock.synchronized (package:synchronized/src/basic_lock.dart:31:26)
E/flutter ( 2952): <asynchronous suspension>
E/flutter ( 2952): #14     ReentrantLock.synchronized (package:synchronized/src/reentrant_lock.dart:28:17)
E/flutter ( 2952): <asynchronous suspension>
E/flutter ( 2952): #15     SqfliteDatabaseFactoryMixin.openDatabase (package:sqflite/src/factory_mixin.dart:66:17)
E/flutter ( 2952): #16     openDatabase (package:sqflite/sqflite.dart:150:26)
E/flutter ( 2952): #17     DBHelper.initDB (package:socialapp/widgets/database_create.dart:36:18)
E/flutter ( 2952): <asynchronous suspension>
E/flutter ( 2952): #18     DBHelper.database (package:socialapp/widgets/database_create.dart:23:25)
E/flutter ( 2952): <asynchronous suspension>
E/flutter ( 2952): #19     DBHelper.createData (package:socialapp/widgets/database_create.dart:54:22)
E/flutter ( 2952): <asynchronous suspension>
E/flutter ( 2952): #20     _writeprofile2State.onPressed (package:socialapp/page/writeprofile2.dart:192:18)
E/flutter ( 2952): #21     _InkResponseState._handleTap (package:flutter/src/material/ink_well.dart:654:14)
E/flutter ( 2952): #22     _InkResponseState.build.<anonymous closure> (package:flutter/src/material/ink_well.dart:729:32)
E/flutter ( 2952): #23     GestureRecognizer.invokeCallback (package:flutter/src/gestures/recognizer.dart:182:24)
E/flutter ( 2952): #24     TapGestureRecognizer._checkUp (package:flutter/src/gestures/tap.dart:365:11)
E/flutter ( 2952): #25     TapGestureRecognizer.handlePrimaryPointer (package:flutter/src/gestures/tap.dart:275:7)
E/flutter ( 2952): #26     PrimaryPointerGestureRecognizer.handleEvent (package:flutter/src/gestures/recognizer.dart:455:9)
E/flutter ( 2952): #27     PointerRouter._dispatch (package:flutter/src/gestures/pointer_router.dart:75:13)
E/flutter ( 2952): #28     PointerRouter.route (package:flutter/src/gestures/pointer_router.dart:102:11)
E/flutter ( 2952): #29     GestureBinding.handleEvent (package:flutter/src/gestures/binding.dart:218:19)
E/flutter ( 2952): #30     GestureBinding.dispatchEvent (package:flutter/src/gestures/binding.dart:198:22)
E/flutter ( 2952): #31     GestureBinding._handlePointerEvent (package:flutter/src/gestures/binding.dart:156:7)
E/flutter ( 2952): #32     GestureBinding._flushPointerEventQueue (package:flutter/src/gestures/binding.dart:102:7)
E/flutter ( 2952): #33     GestureBinding._handlePointerDataPacket (package:flutter/src/gestures/binding.dart:86:7)
E/flutter ( 2952): #34     _rootRunUnary (dart:async/zone.dart:1136:13)
E/flutter ( 2952): #35     _CustomZone.runUnary (dart:async/zone.dart:1029:19)
E/flutter ( 2952): #36     _CustomZone.runUnaryGuarded (dart:async/zone.dart:931:7)
E/flutter ( 2952): #37     _invoke1 (dart:ui/hooks.dart:263:10)
E/flutter ( 2952): #38     _dispatchPointerDataPacket (dart:ui/hooks.dart:172:5)
E/flutter ( 2952):

显然，它在 iOS 上运行良好，但在 Android 上却出现了错误。

我以为是版本问题，所以我更新到最新版本，但仍然出现。

如何解决这个问题？

如果有人能帮助我，我将不胜感激。

4

1 回答 1

0

抛出错误Unhandled Exception: DatabaseException(open_failed /Users/landwhale/Person_Pro_file.db)- 指出访问文件时出现问题。如果提供的路径尚不存在，您可以使用path_provider插件创建，也可以使用getDatabasePath()fromsqflite作为路径。

于 2021-07-07T14:52:11.483 回答