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

Applications of Loaders


Due to its focused nature, applications of Loader are relatively easy to identify. The obvious applications include reading any kind of data from files or databases local to the device, as we've done in the examples in this chapter.

Of course there is no reason that the definition of "loading" should not encompass computing a value or set of values—in the download section of the Packt Publishing website you can find an example that uses Loader to calculate a set of prime numbers.

One strong advantage of Loaders over direct use of AsyncTask is that their lifecycle is very flexible with respect to the Activity and Fragment lifecycles. Without any extra effort we can handle configuration changes such as an orientation change. We can even start loading in one Activity, navigate through the app, and collect the result in a completely separate Activity, if that makes sense for our app.

This decoupling from the Activity lifecycle makes Loader in some ways a better candidate...