由ProxyProvider进行的Flutter注入返回null

Question

GITHUB样本项目

这是我想WebParserApi使用ProxyProvider 注入的简单类，但我得到null，

class RetrievePageSummarizedInformation extends StatesRebuilder {
  BuiltUserProfile builtUserProfile = BuiltUserProfile();
  final WebParserApi _api;

  RetrievePageSummarizedInformation({WebParserApi api}) : _api = api;

  retrievePageProfileInfo(BuildContext context,String username) async {
    //_preparePageProfileCache();
    //WebParserApi _api = Provider.of<WebParserApi>(context);
    return await _api.getProfileRetrieveFromParser(username);
  }

  void _preparePageProfileCache() async {
    await KvStore().createTable('userProfile');
  }
}

主功能：

void main() async {
  Provider.debugCheckInvalidValueType = null;

  _setUpLogging();

  runApp(MultiProvider(providers: providers, child: OKToast(child: StartupApplication())));
}

proxyProvider 实施：

List<SingleChildCloneableWidget> providers = [
    ...independentServices, 
    ...dependentServices, 
    ...uiConsumableProviders
];

List<SingleChildCloneableWidget> independentServices = [
  Provider(
    builder: (_) => WebParserApi.create(),
    dispose: (_, WebParserApi service) => service.client.dispose(),
  )
];

List<SingleChildCloneableWidget> dependentServices = [
  ProxyProvider<WebParserApi, RetrievePageSummarizedInformation>(
    builder: (context, api, retrievePageSummarizedInformation) => RetrievePageSummarizedInformation(api: api),
  )
];

List<SingleChildCloneableWidget> uiConsumableProviders = [

];

这是我的WebParserApi类实现：

@ChopperApi(baseUrl: '/')
abstract class WebParserApi extends ChopperService {
  @Get(path: '{token}')
  Future<Response<BuiltUserProfile>> getProfileRetrieveFromParser(@Path() String username);

  static WebParserApi create() {
    final client = ChopperClient(
        client: http.IOClient(
          HttpClient()..connectionTimeout = const Duration(seconds: 60),
        ),
        baseUrl: 'https://www.sample.com',
        services: [
          _$WebParserApi(),
        ],
        converter: BuiltValueConverter(),
        interceptors: [
          HeadersInterceptor({'Content-Type': 'application/json'}),
          HttpLoggingInterceptor(),
        ]);
    return _$WebParserApi(client);
  }
}

问题在这里。注入WebParserApi到RetrievePageSummarizedInformation类：

return Injector<RetrievePageSummarizedInformation>(
  models: [() => RetrievePageSummarizedInformation()],
  builder: (context, model) => Stack(
    children: <Widget>[
      ),
    ],
  ),
);

我在github上的此链接https://github.com/MahdiPishguy/proxy_provider_sample上创建了一个简单项目，因为当我尝试使用_pageInformation.pageProfile（'test'）;时，PageInformation类的_api变量为null。在主要班级

Answer 1

我的问题解决了，我们必须Provider.of(context)在定义的类上使用ProxyProvider

class RetrievePageSummarizedInformation extends StatesRebuilder {
  BuiltUserProfile builtUserProfile = BuiltUserProfile();
  final WebParserApi _api;

  RetrievePageSummarizedInformation({@required WebParserApi api}) : _api = api;

  getPageProfileInfo(String username) async {
    final res = await _api.getSimpleProfileInformation(username);
    return res;
  }
}

注射液：

models: [() => RetrievePageSummarizedInformation(api:Provider.of(context))],