상황

클린 아키텍쳐 따라가면서 프로젝트 진행하던 도중, viewModel 에 접근해서 상태값 변경하려고 했다. 갑자기 Provider<모델> 을 접근할 수없으니
다른 방식으로 접근해봐라 라는 의미이다.

Error: Could not find the correct Provider<SearchViewModel> above this SearchScreen Widget

This happens because you used a `BuildContext` that does not include the provider
of your choice. There are a few common scenarios:

- You added a new provider in your `main.dart` and performed a hot-reload.
  To fix, perform a hot-restart.

- The provider you are trying to read is in a different route.

  Providers are "scoped". So if you insert of provider inside a route, then
  other routes will not be able to access that provider.

- You used a `BuildContext` that is an ancestor of the provider you are trying to read.

  Make sure that SearchScreen is under your MultiProvider/Provider<SearchViewModel>.
  This usually happens when you are creating a provider and trying to read it immediately.

  For example, instead of:

  Widget build(BuildContext context) {
    return Provider<Example>(
      create: (_) => Example(),
      // Will throw a ProviderNotFoundError, because `context` is associated
      // to the widget that is the parent of `Provider<Example>`
      child: Text(context.watch<Example>().toString()),
    );
  }

해결 방법

di 폴더를 만들어서 의존성을 주입해주자.

import 'package:provider/provider.dart';
import 'package:what_do_you_want_to_sing/presentation/search/search_view_model.dart';

// 이곳에서 의존성을 한번에 불러 생성한 다음, main.dart 에 주입하겠다.
List<ChangeNotifierProvider<SearchViewModel>> getProviders() {
  SearchViewModel searchViewModel = SearchViewModel();

  return [
    ChangeNotifierProvider(create: (_) => searchViewModel),
  ];
}

void main() {
  // provider 호출
  final providers = getProviders();

  runApp(
    MultiProvider(
      providers: providers,
      child: const MyApp(),
    ),
  );
}