RxAndroid: Fetch data from multiple apis-CodePudding

I have a usecase where I get list of userids from 1 Api as a Single<List> and I need to fetch all the users from a different Api which returns Single.

fun fetchUserIds(): Single<List<String>>

fun fetchUser(id: String): Single<User>

I need to return a List eventually. What is the ideal way to do this using RxJava?

CodePudding user response：

You can use Flowable to iterate over the userIds and call the fetchUser on each element. Then you can combine the result (e.g toList or collect):

fetchUserIds()
  .flatMap(ids -> Flowable.fromIterable(ids).flatMapSingle(this::fetchUser).toList())
  .subscribe(users -> {
      //list of users
   });