Book Image

RxJava Essentials

By : Ivan Morgillo
Book Image

RxJava Essentials

By: Ivan Morgillo

Overview of this book

<p>RxJava—Reactive Extensions for the JVM—is a library for composing asynchronous and event-based programs using Observable sequences for the Java VM, which will help you beat Android platform limitations to create astonishing Android apps.</p> <p>Starting with some quick background information on the Rx .NET library, this book quickly moves on to your first example. You will understand Observables and learn to filter, transform, or merge them in detail. Next, you will learn how to get rid of Threads, AsyncTasks, and Handlers with Schedulers to create a smooth user experience. Develop an easy, ready-to-go approach to REST API communications and enrich your skills by working with new challenging examples.</p> <p>By the end of the book, you will have explored the reactive programming world and will have created your first Android app without having to think about threading, networking, concurrency, and collection management.</p> <p>The images have been taken from&nbsp;<a href="http://reactivex.io/" target="_blank">http://reactivex.io/</a> which is licensed under a Create Commons 3.0 Attribution license (<a href="https://creativecommons.org/licenses/by/4.0/" target="_blank">https://creativecommons.org/licenses/by/4.0/</a>)</p>
Table of Contents (15 chapters)

Switch


There could be complex scenarios wherein we should be able to automatically unsubscribe from an Observable to subscribe to a new one in a continuous subscribe-unsubscribe sequence.

RxJava's switch(), as per the definition, transforms an Observable emitting Observables into an Observable emitting the most recent emitted Observable.

Given a source Observable that emits a sequence of Observables, switch() subscribes to the source Observable and starts emitting the same items emitted by the first emitted Observable. When the source emits a new Observable, switch() immediately unsubscribes from the old Observable (thus interrupting the item flow from it) and subscribes to the new one, starting to emit its items.