BehaviorSubject 处理中的 BehaviorSubject

Question

场景我有一个 Territories 列表，我想获取每个 Territory 中的所有 Items从服务器。所以，我决定用BehaviorSubject试试看。我不知道我是不是 "Insane"。这就是我所做的：

private Observable<ItemListResponse> getItemByTerritory() {

    List<String> territories = PrefUtils.getUserTerritories(context);

    BehaviorSubject<Integer> territoryControl = BehaviorSubject.<Integer>create(0);
    Observable<ItemListResponse> territoryRet = territoryControl.asObservable().concatMap(integer -> {

        if (integer != territories.size()) {

            BehaviorSubject<Integer> ret = BehaviorSubject.create(1);
            return ret.asObservable().concatMap(integer1 -> {

                if (integer > 0) {
                    return bakeryAPI.getBakeries("Bearer " + PrefUtils.getToken(context), integer1, 21, territories.get(integer))
                            .subscribeOn(Schedulers.io())
                            .observeOn(AndroidSchedulers.mainThread())
                            .doOnNext(itemListRespont -> {
                                if (itemListRespont.getItemResponse().getMeta().getPage() != itemListRespont.getItemResponse().getMeta().getPageCount() && itemListRespont.getItemResponse().getMeta().getPageCount() > 0) {
                                    ret.onNext(integer1 + 1);
                                } else {
                                    ret.onNext(-1);
                                    territoryControl.onNext(integer + 1);
                                }
                            });
                } else {
                    return Observable.<ItemListResponse>empty().doOnCompleted(ret::onCompleted);
                }
            });
        } else {
            return Observable.<ItemListResponse>empty().doOnCompleted(territoryControl::onCompleted);
        }
    });
    return Observable.defer(() -> territoryRet);
}

它所做的只是挂起，就像我这样做时什么都没有运行

public void getItemByTerritory(APIRequestListener apiRequestListener){
    realm.executeTransaction(realm1 -> realm1.where(RealmItem.class).findAll().deleteAllFromRealm());

    getItemByTerritory().subscribe(new Subscriber< ItemListResponse >() {
        @Override
        public void onCompleted() {
            Log.e(TAG, "Completed Bakery");
            apiRequestListener.completed();
            unsubscribe();
        }

        @Override
        public void onError(Throwable e) {
            e.printStackTrace();
            apiRequestListener.handleError(e);
        }

        @Override
        public void onNext(ItemListResponse itemListRespont) {
        }
    });
}

Answer 1

如果我的理解正确并且您想要的是获取 getBakeries 响应的页面，那么以下递归函数调用应该可以解决问题：

private Observable<ItemListResponse> getItemByTerritory() {
    List<String> territories = PrefUtils.getUserTerritories(context);
    return Observable.from(territories).flatMap(territory -> fetchTerritoryPage(territory, 0));
}

private Observable<ItemListResponse> fetchTerritoryPage(String territory, int page) {
    System.out.println("Fetch territory page " + page);
    return bakeryAPI.getBakeries("Bearer " + PrefUtils.getToken(context), page, 21, territory).flatMap(response
            -> {
        final ItemListResponse.ItemResponse.Meta meta = response.getItemResponse().getMeta();
        final Observable<ItemListResponse> thisPage = Observable.just(response);
        if (page < meta.getPageCount()) {
            final Observable<ItemListResponse> nextPage = fetchTerritoryPage(territory, page + 1);
            return thisPage.concatWith(nextPage);
        } else {
            return thisPage;
        }
    });
}

注意 fetchTerritoryPage 如何递归调用自身来获取下一页。

BehaviorSubject 处理中的 BehaviorSubject

BehaviorSubject within a BehaviorSubject handling

android

retrofit

rx-java

behaviorsubject