[Day24] Flutter - Application Login (part8)

前言

Hi, 我是鱼板伯爵这里我们要将Google登入与介面做连接，所以又要使用Bloc了，老样子按照着Event->State->Bloc的步骤建筑起来吧。

完整程序码

需要具备的知识

• 专案架构 (Domain Driven Design)
• 管理程序码好帮手 ( Bloc )
• 基本元件应用

Login：Event

由於我只实作Google登入所以只有一个Google登入的事件，如果你有其他的可以继续扩充。

part of 'sign_in_bloc.dart';

abstract class SignInEvent extends Equatable {
  const SignInEvent();

  @override
  List<Object> get props => [];
}

class LoginWithGooglePressed extends LoginEvent {}

Login：State

状态分成三个登入成功、登入失败和登入中，如果你是使用输入帐密的登入话，还可以在里面加一些参数来检查是帐号没输入还是密码没输入等等，这样可以在UI上显示错误讯息。

part of 'sign_in_bloc.dart';

abstract class SignInState extends Equatable {
  const SignInState();

  @override
  List<Object> get props => [];
}

class SignInStateInitial extends SignInState {}

class SignInStateLoading extends SignInState {}

class SignInStateFailure extends SignInState {}

class SignInStateSuccess extends SignInState {}

Login：Bloc

登入然後检查成功或失败，这就是等等我们按钮触发事件时会执行的任务。

import 'dart:async';
import 'dart:developer';

import 'package:bloc/bloc.dart';
import 'package:equatable/equatable.dart';
import 'package:stunning_tribble/infrastructure/auth/auth_repository.dart';

part 'sign_in_event.dart';
part 'sign_in_state.dart';

class SignInBloc extends Bloc<SignInEvent, SignInState> {
  AuthRepository _userRepository;

  SignInBloc({
    required AuthRepository userRepository,
  })  : _userRepository = userRepository,
        super(SignInStateInitial());

  @override
  Stream<SignInState> mapEventToState(
    SignInEvent event,
  ) async* {
    if (event is SignInWithGooglePressed) {
      yield* _mapLoginWithGooglePressedToState();
    }
  }

  Stream<SignInState> _mapLoginWithGooglePressedToState() async* {
    final user = await _userRepository.signInWithGoogle();
    yield* user.fold(
      (failure) async* {
        log("$failure");
        yield SignInStateFailure();
      },
      (success) async* {
        yield SignInStateSuccess();
      },
    );
  }
}