Tagakov

How do I transform observable's error to another observable?

I am trying to implement algorithm showed on scheme below:

![Block scheme][1]


  [1]: http://i.stack.imgur.com/777p5.png

I am using a tutorial named Grokking RxJava to start my learning and found that flatMap operator can convert one Observable returning by Retrofit into another which allows me to do a chain of invocations of server methods. But in the tutorial chaining methods always return success result. **How I can do the same chaining if one of the remote methods returns error?**

Tagakov

package com.tagakov.testapplication;

import android.animation.ValueAnimator;
import android.annotation.TargetApi;
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.PorterDuff;

Tagakov

package com.tagakov.testapplication;

import android.animation.ValueAnimator;
import android.annotation.TargetApi;
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.BitmapShader;
import android.graphics.Canvas;

Tagakov

import android.app.Activity;
import android.app.Application;
import android.content.Context;
import android.hardware.SensorManager;
import android.os.Bundle;
import android.os.Handler;
import android.os.Looper;
import android.os.Vibrator;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;

Tagakov

import timber.log.Timber;

public class DebugTreeWithCodeLink extends Timber.DebugTree {

    private final ThreadLocal<String> codeLink = new ThreadLocal<>();
    private static final int CALL_STACK_INDEX = 5;

    @Override
    protected String createStackElementTag(StackTraceElement element) {
        codeLink.set(createCodeLink(element));

Tagakov

public class PagerLayoutManager extends LinearLayoutManager {

    private static final int SETTLE_DURATION = 600;
    private static final float DEFAULT_FLING_THRESHOLD_DP = 10f;

    private final int flingThreshold;

    private int scrollState;

    public PagerLayoutManager(Context context) {

Tagakov

#!/usr/bin/env bash

REMOTE_MACHINE=${1}
APPLICATION_MODULE=${2}

ASSEMBLE_COMMAND=${3}
ASSEMBLE_TESTS_COMMAND=${4}

ANDROID_SDK_VERSION=${5}

Tagakov

fun <T> magic(jobs: Observable<Completable>, hot: Observable<T>): Observable<T> {
  return Observable.switchOnNext(jobs.map { it.andThen(hot) }.startWith(hot))
}

Tagakov

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(new FrameLayout(this) {{
            setId(42);
        }});
        
        if (savedInstanceState == null) {

Tagakov

typealias Epic<State> = (actions: Observable<Action>, currentState: CurrentState<State>) -> Observable<Action>
typealias CurrentState<State> = () -> State

class EpicMiddleware<State: Any> constructor(): Middleware<State> {
    private val epics = PublishSubject.create<Epic<State>>()

    override fun invoke(store: Store<State>, nextDispatcher: Dispatcher) : Dispatcher {
        val actions = PublishSubject.create<Action>()
        epics