Android RxJava：链接两个请求并在其间做一些逻辑

Question

您好，我正在尝试使用平面图创建网络请求链，但不太了解如何执行此操作的过程。

目标是这样做：

执行网络请求 1 一旦我从 networkRequestOne 获得结果，对该结果执行一些逻辑，然后执行下一个 networkRequestTwo 并使用从 networkRequestTwo 返回的响应值调用 onSuccess。

当前代码：

delegator.requestOne(requestData)
                .flatMap ({  response ->
                    if(response.isSuccessful){
                        cookieStorage.saveSessionCookies(response.header(cookieStorage.COOKIE_HEADER_NAME)!!)
                    }
                    return delegator.requestTwo

                })
                .observeOn(AndroidSchedulers.mainThread())
                .subscribeOn(Schedulers.io())
                .subscribe(object : SingleObserver<ResponseTwo>() {
                    @Override
                    fun onSubscribe(Disposable d) {
                    }

                    @Override
                    fun onSuccess(responseTwo :ResponseTwo) {
                        callback.onSuccess(responseTwo)
                    }

                    @Override
                    public void onError(Throwable e) {

                    }
                });

delegator.requestOne 和 delegator.requestTwo 都连接到 returns 单个可观察对象

的改造调用

Answer 1

这有点奇怪，您需要在 subscribe 方法中调用回调。如果您已经有了 Rx，为什么还需要 cb？如果你 return a Single 和运行你实际订阅的回调代码会更清楚：

...
// don't forget to handle the `disposable`
doSmth(requestData)
    .subscribeOn(Schedulers.io())
    .observeOn(AndroidSchedulers.mainThread())
    .subscribe(
            { success -> /* here's your success callback code */},
            { error -> /* handle error here */}
    )
...

fun doSmth(requestData: RequestData): Single<ResponseTwo> = delegator.requestOne(requestData)
        .doOnSuccess(::updateCookies)
        // you can extract the data you need from the first request using `it`
        .flatMap { delegator.requestTwo() }

fun updateCookies(response: Response<ResponseOne>) {
    val cookie = response.header(cookieStorage.COOKIE_HEADER_NAME)!!
    cookieStorage.saveSessionCookies(cookie)
}

更新

如果你还需要callback:

// don't forget to handle the `disposable`
delegator.requestOne(requestData)
        .doOnSuccess(::updateCookies)
        .flatMap { delegator.requestTwo() }
        .observeOn(AndroidSchedulers.mainThread())
        .subscribeOn(Schedulers.io())
        .subscribe(
                { success -> callback.onSuccess(success) },
                { error -> callback.onError(error) }
        )

fun updateCookies(response: Response<ResponseOne>) {
    if (response.isSuccessful) {
        val cookie = response.header(cookieStorage.COOKIE_HEADER_NAME)!!
        cookieStorage.saveSessionCookies(cookie)
    }
}

Android RxJava：链接两个请求并在其间做一些逻辑

Android RxJava: Chaining two requests and doing some logic inbetween

android

kotlin

flatmap

retrofit2

rx-java2