Book Image

Asynchronous Android Programming - Second Edition

By : Steve Liles
Book Image

Asynchronous Android Programming - Second Edition

By: Steve Liles

Overview of this book

Asynchronous programming has acquired immense importance in Android programming, especially when we want to make use of the number of independent processing units (cores) available on the most recent Android devices. With this guide in your hands you’ll be able to bring the power of Asynchronous programming to your own projects, and make your Android apps more powerful than ever before! To start with, we will discuss the details of the Android Process model and the Java Low Level Concurrent Framework, delivered by Android SDK. We will also guide you through the high-level Android-specific constructs available on the SDK: Handler, AsyncTask, and Loader. Next, we will discuss the creation of IntentServices, Bound Services and External Services, which can run in the background even when the user is not interacting with it. You will also discover AlarmManager and JobScheduler APIs, which are used to schedule and defer work without sacrificing the battery life. In a more advanced phase, you will create background tasks that are able to execute CPU-intensive tasks in a native code-making use of the Android NDK. You will be then guided through the process of interacting with remote services asynchronously using the HTTP protocol or Google GCM Platform. Using the EventBus library, we will also show how to use the Publish-Subscribe software pattern to simplify communication between the different Android application components by decoupling the event producer from event consumer. Finally, we will introduce RxJava, a popular asynchronous Java framework used to compose work in a concise and reactive way. Asynchronous Android will help you to build well-behaved applications with smooth responsive user interfaces that delight the users with speedy results and data that’s always fresh.
Table of Contents (19 chapters)
Asynchronous Android Programming Second Edition
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
2
Performing Work with Looper, Handler, and HandlerThread
Index

Sending upstream messages


Although we are able to receive the chat group messages, we are not able to interact with the message stream from the application. Additionally, to send and process upstream messages with the GCM platform, an application server that implements the XMPP Connection Server protocol is required to connect to the GCM servers and receive upstream XMPP messages.

To deal with our group messages we built a very basic XMPP server that processes the upstream messages from the device and forwards the message to the topic message.

The basic XMPP Server source code is available from the Packt Publishing website. Grab it from the Packt website, and, before you run it, update the static fields with your SenderID and your ServerKey in the GCMServer.java class file.

private static final String SENDER_ID = "<YOUR_SENDER_ID>"; 
private static final String SERVER_KEY = "<SERVER_KEY>";

The server will connect to the GCM platform, initiate a XMPP session, and process all the...