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

Common AsyncTask issues


As with any powerful programming abstraction, AsyncTask is not entirely free from issues and compromises.

Fragmentation issues

In the Controlling the level of concurrency section, we saw how AsyncTask has evolved with new releases of the Android platform, resulting in behavior that varies with the platform of the device running the task, which is a part of the wider issue of fragmentation.

The simple fact is that if we target a broad range of API levels, the execution characteristics of our AsyncTasks—and therefore, the behavior of our apps—can vary considerably on different devices. So what can we do to reduce the likelihood of encountering AsyncTask issues due to fragmentation?

The most obvious approach is to deliberately target devices running at least Honeycomb, by setting a minSdkVersion of 11 in the Android Manifest file. This neatly puts us in the category of devices, which, by default, execute AsyncTasks serially, and therefore, much more predictably.

However,...