如何实现 RxJava 的链式调用--异步中的异步 flatMap

Api.java

public interface Api{
    void queryPhoto(String query,QueryCallback QueryCallback);
    void store(Photo photo,StoreCallback storeCallback);
    interface QueryCallback{
        void onQuerySuccess(List<Photo> photoList);
        void onQueryFailed(Exception e);
    }
    interface StoreCallback{
        void onCatStored(Uri uri);
        void onStoredFailed(Exception e);
    }
}

PhotoUtils.java

RxJob<List<Photo>> queryPhotoJob = new RxJob<List<Photo>>(){
  				@Override
                public void doJob(final RxCallback<List<Photo>> rxCallback) {
                    mApi.queryPhoto("flyer", new Api.QueryCallback() {
                        @Override
                        public void onQuerySuccess(List<Photo> photoList) {
                            rxCallback.onNext(photoList);
                        }
                      

                        @Override
                        public void onQueryFailed(Exception e) {
                            rxCallback.onError(e);
                        }
                    });
                }
            };
};

RxJob<List<Photo>> storePhotoJob = new RxJob<Uri>() {
            @Override
            public void doJob(RxCallback<Uri> rxCallback) {
                mApi.store(photo, new Api.StoreCallback() {
                    @Override
                    public void onCatStored(Uri uri) {
                        rxCallback.onNext(uri);
                    }

                    @Override
                    public void onStoredFailed(Exception e) {
			rxCallback.onError(e);
                    }
                });
            }
        };


queryPhotoJob.map(photoList -> { return getBestPhoto(photoList);})
  	.flatMap(photo -> { return storePhotoJob;} )
	.map(photo -> {return photo.getUrl();})
	.doJob(new RxCallback<String>() {
            @Override
            public void onNext(String s) {
		ToastUtils.show(s);
            }

            @Override
            public void onError(Exception e) {
		ToastUtils.show(e);
            }
   });

RxJob.java

public abstract class RxJob<T>{
	public abstract void doJob(RxCallback<T> rxCallback){}
  	public RxJob map(){
        final RxJob<T> curJob = this;
        return new RxJob<R>() {
            @Override
            public void doJob(final RxCallback<R> rxCallback) {
                curJob.doJob(new RxCallback<T>() {
                    @Override
                    public void onNext(T t) {
                        R mapped = func.call(t);
                        rxCallback.onNext(mapped);
                    }

                    @Override
                    public void onError(Exception e) {
                        rxCallback.onError(e);
                    }
                });
            }
        };
    }
  	public RxJob flatMap(){...};
}

========================================================

最后

记录一些 RxJava 相关的文章内容

RxJava 中的 contactMap 和 flatMap 区别

========================================================