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Cara membuat Aplikasi Internasionalisasi Offline:Gunakan database Sqlite

https://pub.dev/packages/floor

Konfigurasikan referensi pubspec.yaml dari perpustakaan dependen dalam proyek Flutter

dependencies:
  flutter:
    sdk: flutter
  floor: ^1.2.0

dev_dependencies:
  floor_generator: ^1.2.0
  build_runner: ^2.1.2

Buat entitas dan lihat [project_root]/lib/app/data/entity/vegetalbe.dart

import 'package:floor/floor.dart';

@Entity(tableName: "vegetables")
class Vegetable {
  @PrimaryKey(autoGenerate: true)
  final int? id;

  final String name;

  final String locale;

  final String desc;

  @ColumnInfo(name: 'created_at')
  final int createTime;

  @ColumnInfo(name: 'updated_at')
  final int updateTime;

  Vegetable(
    this.id,
    this.name,
    this.locale,
    this.desc, {
    int? createTime,
    int? updateTime,
  })  : this.createTime = createTime ?? DateTime.now().millisecondsSinceEpoch,
        this.updateTime = updateTime ?? DateTime.now().millisecondsSinceEpoch;
}

@DatabaseView(
    'SELECT v.id,   v.name, v.desc, v.locale,   uf.hash,    uf.ext,     v.created_at,   v.updated_at from   vegetables v LEFT OUTER JOIN upload_file_morph ufm on   v.id = ufm.related_id LEFT OUTER JOIN upload_file uf on ufm.upload_file_id = uf.id;',
    viewName: "vegetables_v")
class VegetableV {
  final int id;
  final String name;
  final String locale;
  final String? desc;
  final String? hash;
  final String? ext;

  @ColumnInfo(name: 'created_at')
  final int createTime;

  @ColumnInfo(name: 'updated_at')
  final int updateTime;

  VegetableV(
    this.id,
    this.name,
    this.locale,
    this.desc,
    this.hash,
    this.ext, {
    int? createTime,
    int? updateTime,
  })  : this.createTime = createTime ?? DateTime.now().millisecondsSinceEpoch,
        this.updateTime = updateTime ?? DateTime.now().millisecondsSinceEpoch;
}

Untuk detail spesifik, silakan merujuk ke https://floor.codes/database-views/

Buat "Objek Akses Data" sesuai dengan tampilan[project_root]/lib/app/data/dao/vegetalbe_dao.dart

import 'package:floor/floor.dart';
import 'package:strapi_flutter_internation_poc/app/data/entity/vegetable.dart';

@dao
abstract class VegetableDao {
  @Query('SELECT * FROM vegetables_v')
  Future<List<VegetableV>> findAll();
}

Buat kelas manajemen Database [project_root]/lib/app/data/database.dart

import 'dart:async';
import 'package:floor/floor.dart';
import 'package:sqflite/sqflite.dart' as sqflite;
// daos
import 'dao/vegetable_dao.dart';
// entitys
import 'entity/vegetable.dart';

part 'database.g.dart'; // the generated code will be there

@Database(version: 1, entities: [Vegetable], views: [VegetableV])
abstract class AppDatabase extends FloorDatabase {
  VegetableDao get vegetableDao;
}

Jalankan generator kode Lantai

flutter packages pub run build_runner build
[INFO] Generating build script...
[INFO] Generating build script completed, took 480ms

[INFO] Initializing inputs
[INFO] Reading cached asset graph...
[INFO] Reading cached asset graph completed, took 67ms

[INFO] Checking for updates since last build...
[INFO] Checking for updates since last build completed, took 651ms

[INFO] Running build...
[INFO] 1.1s elapsed, 0/1 actions completed.
[INFO] 2.2s elapsed, 0/1 actions completed.
[INFO] 4.0s elapsed, 0/1 actions completed.
[INFO] 8.4s elapsed, 0/1 actions completed.
[INFO] Running build completed, took 8.8s

[INFO] Caching finalized dependency graph...
[INFO] Caching finalized dependency graph completed, took 34ms

[INFO] Succeeded after 8.8s with 2 outputs (2 actions)

Ini akan menghasilkan database.g.dart dalam direktori yang sama dengan database.dart

Gunakan skema Layanan GetX untuk membuat layanan db [project_root]/lib/app/common/services/db_service.dart.dart

Harap beri perhatian khusus di sini

Berbeda dengan dokumentasi resmi Lantai, Lantai akan menghasilkan database sqlite berdasarkan entitas. Saya akan memberikan file database yang ada ke Lantai untuk digunakan tanpa membuat file database baru.

import 'dart:io';
import 'package:get/get.dart';
import 'package:path/path.dart';
import 'package:floor/floor.dart';
import 'package:flutter/services.dart';
import 'package:sqflite/sqflite.dart';
import 'package:strapi_flutter_internation_poc/app/data/database.dart';

class DbService extends GetxService {
  static DbService get to => Get.find();

  late AppDatabase db;

  Future<DbService> init() async {
    final callback = Callback(
      onCreate: (database, version) {},
      onOpen: (database) {
        print('onOpen database');
        getDatabasesPath().then((value) => print(value));
      },
      onUpgrade: (database, startVersion, endVersion) {},
    );

    var dbDir = await getDatabasesPath();
    var dbPath = join(dbDir, "app_database.db");

    await deleteDatabase(dbPath);

    ByteData data = await rootBundle.load("assets/db/data.db");
    List<int> bytes =
        data.buffer.asUint8List(data.offsetInBytes, data.lengthInBytes);
    await File(dbPath).writeAsBytes(bytes);

    db = await $FloorAppDatabase
        .databaseBuilder(dbPath)
        .addCallback(callback)
        .build();
    return this;
  }
}

Instansiasi DbService [project_root]/lib/main.dart

Future<void> main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await initServices();

  runApp(
    GetMaterialApp(
      title: "Application",
      initialRoute: AppPages.INITIAL,
      getPages: AppPages.routes,
    ),
  );
}

Future<void> initServices() async {
  print('starting services ...');
  await Get.putAsync(() => DbService().init());
  print('All services started...');
}

Ubah kode home_controller untuk membaca database Sqlite [project_root]/lib/app/modules/home/controllers/home_controller.dart

import 'package:get/get.dart';
import 'package:strapi_flutter_internation_poc/app/common/services/db_service.dart';
import 'package:strapi_flutter_internation_poc/app/data/entity/vegetable.dart';

class HomeController extends GetxController {
  final vegetables = Rx<List<VegetableV>>([]);

  @override
  void onInit() {
    super.onInit();
  }

  @override
  void onReady() {
    super.onReady();
  }

  Future<void> getAllVegetables() async {
    final result = await DbService.to.db.vegetableDao.findAll();
    vegetables.value = result;
  }

  @override
  void onClose() {}
}

Tes sebentar

controller.getAllVegetables();

  Future<void> getAllVegetables() async {
    final result = await DbService.to.db.vegetableDao.findAll();
    vegetables.value = result;
    print(result);
  }

keluar

I/flutter ( 7396): starting services ...
I/flutter ( 7396): onOpen database
I/flutter ( 7396): /data/user/0/com.nasawz.strapi_flutter_internation_poc.strapi_flutter_internation_poc/databases
I/flutter ( 7396): All services started...
[GETX] Instance "DbService" has been created
[GETX] Instance "DbService" has been initialized
[GETX] Instance "GetMaterialController" has been created
[GETX] Instance "GetMaterialController" has been initialized
[GETX] GOING TO ROUTE /home
[GETX] Instance "HomeController" has been created
[GETX] Instance "HomeController" has been initialized
I/flutter ( 7396): [Instance of 'VegetableV', Instance of 'VegetableV', Instance of 'VegetableV', Instance of 'VegetableV', Instance of 'VegetableV', Instance of 'VegetableV', Instance of 'VegetableV', Instance of 'VegetableV']

kesuksesan! Data dibacakan.

Gunakan fitur Obx GetX untuk menampilkan data pada antarmuka

import 'package:flutter/material.dart';

import 'package:get/get.dart';
import '../controllers/home_controller.dart';

class HomeView extends GetView<HomeController> {
  @override
  Widget build(BuildContext context) {
    controller.getAllVegetables();
    return Scaffold(
      appBar: AppBar(
        title: Text('Vegetables'),
        centerTitle: true,
      ),
      body: Obx(() => ListView.builder(
          itemCount: controller.vegetables.value.length,
          itemBuilder: (context, index) {
            var vegetable = controller.vegetables.value[index];
            return Padding(
              padding: const EdgeInsets.all(18.0),
              child: Container(
                child: Row(
                  children: [
                    Container(
                      // color: Colors.red,
                      child: Image.asset(
                        'strapi/public/uploads/thumbnail_${vegetable.hash}${vegetable.ext}',
                        fit: BoxFit.contain,
                        width: 140,
                        height: 140,
                      ),
                    ),
                    Container(
                      width: Get.width - 18 * 2 - 140 - 18,
                      child: Column(
                        crossAxisAlignment: CrossAxisAlignment.start,
                        children: [
                          Text(
                            vegetable.name,
                            style: Get.textTheme.headline6,
                          ),
                          Text(
                            vegetable.desc!,
                            style: Get.textTheme.subtitle1,
                            maxLines: 1,
                            overflow: TextOverflow.ellipsis,
                          ),
                        ],
                      ),
                    ),
                  ],
                ),
              ),
            );
          })),
    );
  }
}


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