Multiple requests with retrofit to combine results

Question

Im using retrofit (1.9) and trying to work out how i can call 2 apis and merge the results.

I guess the results should be merged when last api has finished returning a response...

How can i do this?

Udpate, as per Antons answer I have tried the following:

added to gradle:

  compile 'io.reactivex:rxjava:1.0.+'
    compile 'io.reactivex:rxandroid:0.23.+'

Api interface

 @GET("/maps/api/place/details/json")
    Observable<PlaceDetailResult1> getPlacesFrom1( @Query("key") String key,  @Query("placeid") String placeid);


@GET("api/places/{id}/ratings")
Observable<PlaceDetailResult2> getPlacesFrom2(@Path("id") String id);

In fragment

     IPlaces api = adapter.create(IPlaces.class); //endpoint1
     IPlaces api2 = adapter2.create(IPlaces.class); //endpoint2

    Observable.combineLatest(
            api.getPlacesFrom1("key", placeId),
            api2.getPlacesFrom2(placeId),
        new Func2<PlaceDetailResult1, PlaceDetailResult2, MergedReviews>() {
            @Override
            public MergedReviews call(PlaceDetailResult placeDetailResult1, PlaceDetailResult2 placeDetailResult2) {
                // processToMerge(  placeDetailResult1, placeDetailResult2)
                return mr;
            }

            })
            .subscribeOn(Schedulers.newThread())
            .observeOn(AndroidSchedulers.mainThread())
            .subscribe(new Observer<MergedReviews>() {
                @Override
                public void onCompleted() {

                }

                @Override
                public void onError(Throwable e) {

                }

                @Override
                public void onNext(MergedReviews mr) {

                    SetAdapter(mr.reviews);
                    SetPhotosAdapter(mr.photos);
                }
            });

One thing maybe worth noting, when I added RxJava to gradle i was getting some error, which went away after I did multiDexEnabled true in the gradle file

Answer 1

You can use RxJava and combine results like this: Combining API calls with RX Java

Here is tutorial, how to use RxJava and Retrofit 1.9: http://randomdotnext.com/retrofit-rxjava/