Book Image

Asynchronous Android

By : Steve Liles
Book Image

Asynchronous Android

By: Steve Liles

Overview of this book

With more than a million apps available from Google Play, it is more important than ever to build apps that stand out from the crowd. To be successful, apps must react quickly to user input, deliver results in a flash, and sync data in the background. The key to this is understanding the right way to implement asynchronous operations that work with the platform, instead of against it. Asynchronous Android is a practical book that guides you through the concurrency constructs provided by the Android platform, illustrating the applications, benefits, and pitfalls of each.Learn to use AsyncTask correctly to perform operations in the background, keeping user-interfaces running smoothly while avoiding treacherous memory leaks. Discover Handler, HandlerThread and Looper, the related and fundamental building blocks of asynchronous programming in Android. Escape from the constraints of the Activity lifecycle to load and cache data efficiently across your entire application with the Loader framework. Keep your data fresh with scheduled tasks, and understand how Services let your application continue to run in the background, even when the user is busy with something else.Asynchronous Android will help you to build well-behaved apps with smooth, responsive user-interfaces that delight users with speedy results and data that's always fresh, and keep the system happy and the battery charged by playing by the rules.
Table of Contents (14 chapters)
Asynchronous Android
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Building responsive apps with IntentService


The IntentService class is a specialized subclass of Service that implements a background work queue using a single HandlerThread. When work is submitted to an IntentService, it is queued for processing by a HandlerThread, and processed in order of submission.

If the user exits the app before the queued work is completely processed, the IntentService will continue working in the background. When the IntentService has no more work in its queue, it will stop itself to avoid consuming unnecessary resources.

The system may still kill a background app with an active IntentService, if it really needs to (to reclaim enough memory to run the current foreground process), but it will kill lower priority processes first, for example, other non-foreground apps that do not have active services.

The IntentService class gets its name from the way in which we submit work to it: by invoking startService with an Intent.

startService(new Intent(context, MyIntentService...