Book Image

Android 3.0 Application Development Cookbook

By : Kyle Merrifield Mew
Book Image

Android 3.0 Application Development Cookbook

By: Kyle Merrifield Mew

Overview of this book

<p>Android is a mobile operating system that runs on a staggering number of smartphones and tablets. Android offers developers the ability to build extremely rich and innovative applications written using the Java programming language. Among the number of books that have been published on the topic, what&rsquo;s missing is a thoroughly practical, hands-on book that takes you straight to getting your job done without boring you with too much theory.<br /><br />Android 3.0 Application Development Cookbook will take you straight to the information you need to get your applications up and running. This book is written to provide you with the shortest possible route between an idea and a working application. <br /><br />Work through the book from start to finish to become an Android expert, or use it as a reference book by applying recipes directly to your project.<br /><br />This book covers every aspect of mobile app development, starting with major application components and screen layout and design, before moving on to how to manage sensors such as internal gyroscopes and near field communications. Towards the end, it delves into smartphone multimedia capabilities as well as graphics and animation, web access, and GPS. <br /><br />Whether you are writing your first app or your hundredth, this is a book that you will come back to time and time again, with its many tips and tricks on the rich features of Android 3.</p>
Table of Contents (18 chapters)
Android 3.0 Application Development Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Listening for location changes


Obtaining the last known location as we did in the previous recipe is all well and good and handy for retrieving a Location quickly, but it can be unreliable if the handset has been switched off or if the user is on the move. Ideally we want to be able to detect location changes as they happen and to do this we employ a LocationListener.

In this recipe we will create a simple application that keeps track of a mobile device's movements.

Getting ready

This task can be performed most easily by starting where the previous one left off. If you have not completed that task yet, do so now—it is very short—then return here. If you have already completed the recipe then simply open it up to proceed.

How to do it...

  1. First, move the declaration of our LocationManager so that it is a class-wide field:

    LocationManager manager;
  2. In the main Java activity code, before the TextView.setText() call, add the following three lines:

    LocationListener listener = new MyLocationListener();...