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RetrofitとRxJava：2つのリクエストを結合して両方の結果にアクセスする方法は？

サービスに対して2つのリクエストを作成し、結果を組み合わせる必要があります。

ServiceA（）=> [{"id":1,"name":"title"},{"id":1,"name":"title"}]

ServiceB（id）=> {"field":"value","field1":"value"}

現在、結果を結合することができましたが、idをパラメーターとしてServiceBに渡し、最初の結果にアクセスする必要があります。

私がこれまでに試したこと：

   Retrofit repo = new Retrofit.Builder()
                .baseUrl("https://api.themoviedb.org/3/genre/")
                .addConverterFactory(GsonConverterFactory.create())
                .addCallAdapterFactory(RxJavaCallAdapterFactory.create())
                .build();

        Observable<GenerosResponse> Genres  = repo
                .create(services.class)
                .getAllGeneros("movie","list","da0d692f7f62a1dc687580f79dc1e6a0")
                .subscribeOn(Schedulers.newThread())
                .observeOn(AndroidSchedulers.mainThread());

        Observable<ResponseMovies> Movies = repo
                .create(services.class)
                .getAllMovies("28","movies","da0d692f7f62a1dc687580f79dc1e6a0",12)
                .subscribeOn(Schedulers.newThread())
                .observeOn(AndroidSchedulers.mainThread());

        Observable<CollectionsMovies> combined = Observable.Zip(Genres, Movies, new Func2<GenerosResponse, ResponseMovies, CollectionsMovies>() {
            @Override
            public CollectionsMovies call(GenerosResponse generosResponse, ResponseMovies responseMovies) {
                return new CollectionsMovies(generosResponse, responseMovies);
            }
        });

        combined.
                subscribeOn(Schedulers.newThread())
                .observeOn(AndroidSchedulers.mainThread())
                .subscribe(...);

編集

Solution@Maxim Ostrovidovの答えによると：

 private Observable<GenerosResponse> makeRequestToServiceA() {
        return  service.getAllGeneros("movie","list","da0d692f7f62a1dc687580f79dc1e6a0"); //some network call
    }

    private Observable<ResponseMovies> makeRequestToServiceB(Genre genre) {
        return service.getAllMovies(genre.getId(),"movies","da0d692f7f62a1dc687580f79dc1e6a0","created_at.asc"); //some network call based on response from ServiceA
    }

    void doTheJob() {

        makeRequestToServiceA()
        .flatMap(userResponse -> Observable.just(userResponse.getGenres()))      //get list from response
                .flatMapIterable(baseDatas -> baseDatas)
                .flatMap(new Func1<Genre, Observable<? extends ResponseMovies>>() {

                    @Override
                    public Observable<? extends ResponseMovies> call(Genre genre) {
                        return makeRequestToServiceB(genre);
                    }
                }, new Func2<Genre, ResponseMovies, CollectionsMovies>() {

                    @Override
                    public CollectionsMovies call(Genre genre, ResponseMovies responseMovies) {
                        return new CollectionsMovies(genre,responseMovies);
                    }
                }).
                subscribeOn(Schedulers.newThread())
                .observeOn(AndroidSchedulers.mainThread())
                .subscribe(....);
    }
javaandroidrx-javaretrofit2
20
David Hackro

私が理解したように-別のリクエストの結果に基づいてリクエストを作成し、両方の結果を組み合わせる必要があります。そのために、次のflatMap演算子バリアントを使用できます： Observable.flatMap（Func1 collectionSelector、Func2 resultSelector）

指定された関数の結果を、ソースObservableと指定されたコレクションObservableによって発行された値のペアに発行するObservableを返します。 enter image description here

コードを書き換える方法を示す簡単な例：

private Observable<String> makeRequestToServiceA() {
    return Observable.just("serviceA response"); //some network call
}

private Observable<String> makeRequestToServiceB(String serviceAResponse) {
    return Observable.just("serviceB response"); //some network call based on response from ServiceA
}

private void doTheJob() {
    makeRequestToServiceA()
            .flatMap(new Func1<String, Observable<? extends String>>() {
                @Override
                public Observable<? extends String> call(String responseFromServiceA) {
                    //make second request based on response from ServiceA
                    return makeRequestToServiceB(responseFromServiceA);
                }
            }, new Func2<String, String, Observable<String>>() {
                @Override
                public Observable<String> call(String responseFromServiceA, String responseFromServiceB) {
                    //combine results
                    return Observable.just("here is combined result!");
                }
            })
            //apply schedulers, subscribe etc
}

ラムダの使用：

private void doTheJob() {
    makeRequestToServiceA()
            .flatMap(responseFromServiceA -> makeRequestToServiceB(responseFromServiceA),
                    (responseFromServiceA, responseFromServiceB) -> Observable.just("here is combined result!"))
            //...
}
30
Maksim Ostrovidov

探している演算子はflatMap()です

serviceA.getAllGeneros("movie","list","da0d692f7f62a1dc687580f79dc1e6a0")
    .flatMap(genres -> serviceB.getAllMovies(genres.getId() ......))
2
LordRaydenMK