Workshop Flutter

README.md

Flutter - 3 horas de HandsOn

Informações sobre o Workshop

1. Construiremos um aplicativo para gerenciamento de coleções HotWheels e abordaremos:

   • Estrutura básica do Projeto
   • Widget básicos - https://flutter.dev/docs/reference/widgets
   • Requisições a uma API externa (Mattel Inc) - https://pub.dev/packages/dio
   • Salvar informações localmente com banco SQLite para Flutter - https://pub.dev/packages/sqflite
   • Converter objetos JSON para Objetos puros em Dart - https://flutter.dev/docs/development/data-and-backend/json#serializing-json-using-code-generation-libraries
   • Gerenciamento de estado local https://api.flutter.dev/flutter/widgets/State/setState.html
   • Organização de código sem bibliotecas externas - https://medium.com/flutter-community/flutter-code-organization-revised-b09ad5cef7f6

2. Todo participante deve ter o ambiente flutter configurado com a versão estável (1.20.2 em 19/08/2020) e com o projeto hello world rodando em um emulador Para configurar o ambiente, siga as instruções em: https://flutter.dev/docs/get-started/install

3. Usaremos o VSCode para desenvolver nosso projeto. Para isso, é necessário instalar o plugin de Flutter nesta IDE Poderão ser usadas outras IDEs, mas talvez eu não consiga lhe ajudar com os atalhos e particularidades :(

build-runner-helper.md

É necessário anotar a classe com a anotação

@JsonSerializable()

É necessário usar uma partial como:

 part 'my_class.g.dar';

Método para gerar objetos através de um json

 factory MyClass.fromJson(Map<String, dynamic> json) => _$MyClassFromJson(json);

Método para gerar um json através de um objeto

 Map<String, dynamic> toJson() => _$MyClassToJson(this);

Ao adicionar as linhas anteriores, a IDE acusará um erro. Ignore-o por enquanto

Para rodar o build-runner e gerar as classes necessárias para converter json-object / object-json

 flutter pub run build_runner build

No fim sua classe (my_class.dart) deve ser algo como

import 'package:json_annotation/json_annotation.dart';

part 'my_class.g.dart';

@JsonSerializable()
class MyClass {
  final int id;
  
  MyClass({this.id});
  
  factory MyClass.fromJson(Map<String, dynamic> json) => _$MyClassFromJson(json);
  Map<String, dynamic> toJson() => _$MyClassToJson(this);
}

car.dart

import 'package:json_annotation/json_annotation.dart';

part "car.g.dart";

@JsonSerializable()
class Car {
  @JsonKey(name: 'CarMetaID')
  int id;
  @JsonKey(
      name: 'CarOrderNumber', fromJson: int.tryParse, toJson: objectToString)
  int order;
  @JsonKey(name: 'TotalItems')
  int totalItems;
  @JsonKey(name: 'Title')
  String name;
  @JsonKey(name: 'MiniCollectionId')
  int collectionId;
  @JsonKey(name: 'ColorCode')
  String hexColor;
  @JsonKey(name: 'Year')
  int year;
  @JsonKey(name: 'Packagingcode')
  String packageCode;
  @JsonKey(name: 'MainImages')
  List<dynamic> mainImages;

  Car({
    this.id,
    this.order,
    this.name,
    this.totalItems,
    this.hexColor,
    this.year,
    this.packageCode,
    this.mainImages,
  });

  factory Car.fromJson(Map<String, dynamic> json) => _$CarFromJson(json);

  Map<String, dynamic> toJson() => _$CarToJson(this);

  static String objectToString(dynamic v) {
    return String.fromCharCode(v);
  }
}

car.json

{
  "CarMetaID": 102186,
  "CarOrderNumber": "4",
  "TotalItems": 10,
  "Title": "'20 JEEP GLADIATOR",
  "ToyNumber": "GHB41",
  "CarMetaSEOName": "20-jeep-gladiator",
  "CategoryId": null,
  "MiniCollectionId": 1247,
  "MiniCollection": "BAJA BLAZERS",
  "GameCategoryId": 0,
  "GameCategory": null,
  "MiniCollectionUrl": "https://static-nv.mattel.com/HWCarCatalog/en-us/Images/baja-blazers-collection_tcm985-153435.png",
  "MakeUrl": null,
  "ColorUrl": "https://static.mattel.com/HWCarCatalog/en-us/Images/RED_tcm838-287586.png",
  "SeriesUrl": null,
  "ColorSEOName": "red",
  "ColorCode": "#b2020b",
  "MakeSEOName": "jeep",
  "MiniCollectionSEOName": "baja-blazers",
  "Year": 2020,
  "SeriesId": null,
  "Series": null,
  "MakeId": 1156,
  "Make": "Jeep",
  "ColorId": 111,
  "Color": "Red",
  "Packagingcode": "lztsc",
  "CarMetaDescription": null,
  "LiveDate": null,
  "IsNew": 0,
  "DisplayFlag": false,
  "Createddate": "0001-01-01T00:00:00",
  "CreatedBy": null,
  "Modifieddate": null,
  "ModifiedBy": null,
  "Styles": [
    {
      "Id": 1053,
      "Name": "Truck",
      "ImageUrl": "https://static-nv.mattel.com/HWCarCatalog/en-us/Images/Style_Truck_330px_tcm985-127487.png",
      "Number": 1,
      "StyleSEOName": "truck"
    }
  ],
  "ThreeQuarterUnity": [],
  "Sideviewphotos": [
    {
      "URL": "https://media.mattel.com/root/HWCarsCatalog/App/SideView/300x164/GHB41_C_003.png",
      "Resolution": "300X164",
      "ContentId": null
    },
    {
      "URL": "https://media.mattel.com/root/HWCarsCatalog/App/SideView/534x300/GHB41_C_003.png",
      "Resolution": "534X300",
      "ContentId": null
    },
    {
      "URL": "https://media.mattel.com/root/HWCarsCatalog/App/SideView/710x400/GHB41_C_003.png",
      "Resolution": "710X400",
      "ContentId": null
    }
  ],
  "SideviewGIFphotos": [],
  "Topdownphotos": [],
  "UnityImages_iOS": [],
  "UnityImages_Android": [],
  "MainImages": [
    {
      "URL": "https://media.mattel.com/root/HWCarsCatalog/Web/MainImage/GHB41_C_003.png",
      "Resolution": null,
      "ContentId": null
    }
  ],
  "BrandImages": [],
  "ThumbnailImages": [
    {
      "URL": "https://media.mattel.com/root/HWCarsCatalog/Web/Thumbnail/GHB41_C_003.png",
      "Resolution": null,
      "ContentId": null
    }
  ],
  "carouselImages": [],
  "ThreeSixtyDegreeVideo": [],
  "AnimationImage": []
}

car_repository.dart

import 'package:dio/dio.dart';
import 'package:workshop_enterprise/models/car.dart';
import 'package:workshop_enterprise/services/dio_provider_base.dart';

class CarRepository {
  static const String URL_GET_CARS = "GetCars";
  Dio dio = DioProviderBase().dio;

  Future<List<Car>> get(int collectionId) async {
    final _cars = List<Car>();

    Response response = await dio.post(URL_GET_CARS, data: {});

    if (response.statusCode == 200) {
      List.castFrom(response.data).forEach(
        (element) {
          final car = Car.fromJson(element);

          if (car.collectionId == collectionId) {
            _cars.add(car);
          }
        },
      );

      return _cars;
    }

    return null;
  }
}

collection.json

{
  "Id": 1117,
  "Code": "985-120924-1024",
  "Name": "HW CITY WORKS",
  "BackGroundColor": "#fcde07",
  "ForeGroundColor": "#000000",
  "SEOName": "hw-city-works",
  "TotalItems": 10,
  "ImageUrl": "https://static-nv.mattel.com/HWCarCatalog/en-us/Images/HW_Cityworks_330px_tcm985-130360.png"
}

collection_details.dart

import 'package:flutter/material.dart';
import 'package:path/path.dart';
import 'package:sqflite/sqflite.dart';
import 'package:workshop_codecon/models/car.dart';
import 'package:workshop_codecon/models/hw_collection.dart';
import 'package:workshop_codecon/repositories/car_repository.dart';

class CollectionDetails extends StatefulWidget {
  final MiniCollection miniCollection;

  const CollectionDetails({
    Key key,
    this.miniCollection,
  }) : super(key: key);

  @override
  _CollectionDetailsState createState() => _CollectionDetailsState();
}

class _CollectionDetailsState extends State<CollectionDetails> {
  List<int> inCollection = <int>[];
  final carRepo = CarRepository();

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.miniCollection.name),
        centerTitle: true,
      ),
      body: SafeArea(
        child: Container(
          child: FutureBuilder(
            future: carRepo.get(widget.miniCollection.id),
            builder: (context, snapshot) {
              switch (snapshot.connectionState) {
                case ConnectionState.none:
                  continue loading;
                  break;
                loading:
                case ConnectionState.waiting:
                  return Center(
                    child: CircularProgressIndicator(),
                  );
                  break;
                case ConnectionState.active:
                  // TODO: Handle this case.
                  break;
                case ConnectionState.done:
                  List<Car> cars = snapshot.data;

                  return PageView(
                    controller: PageController(initialPage: 1),
                    scrollDirection: Axis.horizontal,
                    children: cars.map((Car car) {
                      return Container(
                        child: Column(
                          mainAxisAlignment: MainAxisAlignment.center,
                          children: <Widget>[
                            if (car.mainImages.length > 0)
                              Image.network(car.mainImages[0]['URL']),
                            Text(car.name),
                            BookmarkIcon(
                              inCollection: inCollection,
                              carId: car.id,
                            )
                          ],
                        ),
                      );
                    }).toList(),
                  );
                  break;
              }
            },
          ),
        ),
      ),
    );
  }
}

class BookmarkIcon extends StatefulWidget {
  List<int> inCollection;
  int carId;

  BookmarkIcon({Key key, this.inCollection, this.carId}) : super(key: key);

  @override
  _BookmarkIconState createState() => _BookmarkIconState();
}

class _BookmarkIconState extends State<BookmarkIcon> {
  final carRepo = CarRepository();

  Database database;

  void loadDB() async {
    var databasesPath = await getDatabasesPath();
    String path = join(databasesPath, 'workshop_codecon.db');

    database = await openDatabase(path, version: 2,
        onCreate: (Database db, int version) async {
      await db.execute('CREATE TABLE carros (id INTEGER)');
    });

    carregarMeusCarros();
  }

  void adicionarCarro(int id) async {
    await database.insert("carros", {'id': id});
  }

  void removeCarro(int id) async {
    await database.delete("carros", where: 'id = ?', whereArgs: [id]);
  }

  void carregarMeusCarros() async {
    List<Map<String, dynamic>> r =
        await database.rawQuery("select * from carros");

    r.forEach((item) {
      widget.inCollection.add(item['id']);
    });

    setState(() {
      widget.inCollection = widget.inCollection;
    });
  }

  @override
  void initState() {
    loadDB();

    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return IconButton(
      icon: Icon(widget.inCollection.contains(widget.carId)
          ? Icons.bookmark
          : Icons.bookmark_border),
      onPressed: () {
        if (widget.inCollection.contains(widget.carId)) {
          widget.inCollection.remove(widget.carId);
          removeCarro(widget.carId);
        } else {
          widget.inCollection.add(widget.carId);
          adicionarCarro(widget.carId);
        }

        setState(() {
          widget.inCollection = widget.inCollection;
        });
      },
    );
  }
}

collection_details_args.dart

import 'package:workshop_enterprise/models/hw_collection.dart';

class CollectionDetailArgs {
  final MiniCollection miniCollection;

  CollectionDetailArgs(this.miniCollection);
}

color_from_hex_string.dart

import 'dart:ui';

extension ColorFromHexString on String {
  Color hexToColor() {
    return Color(int.tryParse(this.replaceAll("#", "0xff")));
  }
}

dio_provider_base.dart

import 'package:dio/dio.dart';

class DioProviderBase {
  static const String URL_BASE = "https://product.mattel.com/api/ProductInfo/";

  static final DioProviderBase _dioProviderBase = DioProviderBase._internal();
  DioProviderBase._internal();

  final dio = Dio(
    BaseOptions(
      baseUrl: URL_BASE,
      connectTimeout: Duration(minutes: 3).inMilliseconds,
      receiveTimeout: Duration(minutes: 5).inMilliseconds,
      headers: {
        "Accept": "application/json",
        "Content-Type": "application/json",
      },
    ),
  );

  factory DioProviderBase() {
    return _dioProviderBase;
  }

  Future<Response> get(String url, Map<String, dynamic> params) async {
    return await dio.get(url, queryParameters: params ?? {});
  }

  Future<Response> post(String url, Map<String, dynamic> bodyData) async {
    return await dio.post(url, data: bodyData ?? {});
  }
}

home_screen.dart

import 'package:flutter/material.dart';
import 'package:workshop_enterprise/models/hw_collection.dart';
import 'package:workshop_enterprise/repositories/mini_collection_repository.dart';
import 'package:workshop_enterprise/screens/collection_details_args.dart';

class HomeScreen extends StatefulWidget {
  @override
  _HomeScreenState createState() => _HomeScreenState();
}

class _HomeScreenState extends State<HomeScreen> {
  final collectionRepo = MiniCollectionRepository();

  @override
  Widget build(BuildContext context) {
    return Material(
      child: SafeArea(
        child: Container(
          child: FutureBuilder(
            future: collectionRepo.get(),
            builder: (context, snapshot) {
              switch (snapshot.connectionState) {
                case ConnectionState.none:
                  continue loading;
                  break;
                loading:
                case ConnectionState.waiting:
                  return Center(
                    child: CircularProgressIndicator(),
                  );
                  break;
                case ConnectionState.active:
                  // TODO: Handle this case.
                  break;
                case ConnectionState.done:
                  return ListView.separated(
                    itemCount: snapshot.data.length,
                    itemBuilder: (context, index) {
                      final MiniCollection miniCollection =
                          snapshot.data[index];
                      return ListTile(
                        leading: SizedBox(
                          width: 40,
                          height: 40,
                          child: Image.network(miniCollection.imageURL),
                        ),
                        trailing: Icon(Icons.chevron_right),
                        title: Text(miniCollection.name),
                        onTap: () {
                          return Navigator.pushNamed(
                            context,
                            '/collectionDetails',
                            arguments: CollectionDetailArgs(miniCollection),
                          );
                        },
                      );
                    },
                    separatorBuilder: (context, index) => Divider(),
                  );
                  break;
              }
              return Text("texto");
            },
          ),
        ),
      ),
    );
  }
}

hw_collection.dart

import 'package:json_annotation/json_annotation.dart';

part "mini_collection.g.dart";

@JsonSerializable()
class MiniCollection {
  @JsonKey(name: 'Id')
  int id;
  @JsonKey(name: 'Name')
  String name;
  @JsonKey(name: 'BackGroundColor')
  String bgColor;
  @JsonKey(name: 'ForeGroundColor')
  String fgColor;
  @JsonKey(name: 'SEOName')
  String seoName;
  @JsonKey(name: 'TotalItems')
  int totalItems;
  @JsonKey(name: 'ImageUrl')
  String imageURL;

  MiniCollection({
    this.id,
    this.name,
    this.bgColor,
    this.fgColor,
    this.seoName,
    this.totalItems,
    this.imageURL,
  });

  factory MiniCollection.fromJson(Map<String, dynamic> json) =>
      _$MiniCollectionFromJson(json);

  Map<String, dynamic> toJson() => _$MiniCollectionToJson(this);
}

mini_collection_repository.dart

import 'package:dio/dio.dart';
import 'package:workshop_enterprise/models/hw_collection.dart';
import 'package:workshop_enterprise/services/dio_provider_base.dart';

class MiniCollectionRepository {
  static const String URL_GET_COLLECTIONS = "GetAllMiniCollection";
  Dio dio = DioProviderBase().dio;

  Future<List<MiniCollection>> get() async {
    final _miniCollections = List<MiniCollection>();

    Response response = await dio.get(URL_GET_COLLECTIONS);

    if (response.statusCode == 200) {
      List.castFrom(response.data).forEach(
        (element) => _miniCollections.add(MiniCollection.fromJson(element)),
      );
      
      return _miniCollections;
    }

    return null;
  }
}

partial_pubspec.yml

dependencies:
  flutter:
    sdk: flutter


  # The following adds the Cupertino Icons font to your application.
  # Use with the CupertinoIcons class for iOS style icons.
  cupertino_icons: ^0.1.3
  dio: ^3.0.10
  json_annotation: ^3.0.1
  sqflite: ^1.3.1

dev_dependencies:
  flutter_test:
    sdk: flutter
  build_runner: ^1.10.0
  json_serializable: ^3.3.0

routes.dart

import 'package:flutter/material.dart';
import 'package:workshop_enterprise/screens/collection_details.dart';
import 'package:workshop_enterprise/screens/collection_details_args.dart';
import 'package:workshop_enterprise/screens/home_screen.dart';

final Map<String, WidgetBuilder> routes = <String, WidgetBuilder>{
  '/': (BuildContext context) => HomeScreen(),
  '/collectionDetails': (BuildContext context) {
    final CollectionDetailArgs args = ModalRoute.of(context).settings.arguments;

    return CollectionDetails(
      miniCollection: args.miniCollection,
    );
  },
};