Reactive Programming on Android with RxJava
Reactive Programming on Android with RxJava
About the Book
Most modern mobile applications require that the user interface be responsive despite simultaneous operations occurring—downloading data over the network, displaying animations, writing files to disk, etc. As a consequence, concurrency and asynchronicity are inherent in mobile programming. Orchestrating concurrent code written in an imperative way, however, is known to be difficult and error-prone. Using the reactive programming paradigm, we are able to simplify much of these needs.
In the Android-world, the leading library for enabling reactive programming is RxJava. RxJava is the backbone of many large-scale applications such as Netflix, Soundcloud, and Trello. This book seeks to explain all there is to know about this topic and its applications in Android development using the latest version of RxJava, RxJava 2.x, by using examples that are familiar to Android developers.
At a high level, you will learn the following concepts:
- The 3 O's—Observable, Operator, Observer
- Alternative base reactive types—Completable, Maybe, Flowable
- Multithreading
- Hot vs. Cold Observables
- Subjects
- Error Handling
- Backpressure
- ...and many more!
If you are using Kotlin to develop Android apps, check out our other book "Reactive Programming on Android with RxKotlin."
Reader Testimonials

Annyce Davis
Android Google Developer Expert
This was a very approachable read versus other books on the subject which have a much more academic feel. By providing several examples and avoiding the typical RxJava jargon, the authors do a great job of helping you to understand the benefits of RxJava and how you can start using it in your Android applications. I truly recommend giving it a read!

David Tiago Conceição
Android Application Engineer
One of the best resources to learn RxJava I have read. A good structure and accessible language makes it great for begginners and for experienced developers to learn basic and advanced topics. Even complex items like error handling and backpressure are described in simplified ways, making easier to understand and to learn deeper details. I recommend the book for everyone that wants to have a better understanding about RxJava and its use cases in Android development.
Table of Contents
-
-
Introduction
- Feedback and Questions
-
Introduction
-
Part 1: RxJava Basics
-
Chapter 1: What is Reactive Programming?
- The History of Reactive Programming
- An Example
-
Chapter 2: RxJava Core Components
- The 3 O’s: Observable, Observer, and Operator
- Marble Diagrams
- Creating an Observable
- Cold vs. Hot Observable
- Lazy Emissions
-
Chapter 3: Operators
- Transforming and Filtering
- Combining
- Aggregating
- Utility Operators
- Reusing Operator Chains
-
Chapter 4: Multithreading
- Asynchronicity
- Schedulers
- Concurrency with FlatMap
-
Chapter 1: What is Reactive Programming?
-
Part 2: RxJava Advanced
-
Chapter 5: Reactive Modeling on Android
- Bridging Non-Reactive into the Reactive world
- Leaving the Reactive world
- The Lazy Approach
- Reactive Everything
- Disposable and the Activity/Fragment Lifecycle
-
Chapter 6: Backpressure
- Fast Producer, Slow Consumer
- Backpressure
- Throttling and Buffering Items
-
Chapter 7: Error Handling
- Errors Along the Chain
- Delivering Errors
- Error-Handling Operators
- Retry Operators
- Undelivered Errors
- Bibliography
-
Chapter 5: Reactive Modeling on Android
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