Book Image

Building Web and Mobile ArcGIS Server Applications with JavaScript ??? Second Edition - Second Edition

By : Eric Pimpler, Mark Lewin
Book Image

Building Web and Mobile ArcGIS Server Applications with JavaScript ??? Second Edition - Second Edition

By: Eric Pimpler, Mark Lewin

Overview of this book

The ArcGIS API for JavaScript enables you to quickly build web and mobile mapping applications that include sophisticated GIS capabilities, yet are easy and intuitive for the user. Aimed at both new and experienced web developers, this practical guide gives you everything you need to get started with the API. After a brief introduction to HTML/CSS/JavaScript, you'll embed maps in a web page, add the tiled, dynamic, and streaming data layers that your users will interact with, and mark up the map with graphics. You will learn how to quickly incorporate a broad range of useful user interface elements and GIS functionality to your application with minimal effort using prebuilt widgets. As the book progresses, you will discover and use the task framework to query layers with spatial and attribute criteria, search for and identify features on the map, geocode addresses, perform network analysis and routing, and add custom geoprocessing operations. Along the way, we cover exciting new features such as the client-side geometry engine, learn how to integrate content from ArcGIS.com, and use your new skills to build mobile web mapping applications. We conclude with a look at version 4 of the ArcGIS API for JavaScript (which is being developed in parallel with version 3.x) and what it means for you as a developer.
Table of Contents (21 chapters)
Title Page
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Customer Feedback
Preface

Integrating the geolocation API


You can use the HTML5 geolocation API in your ArcGIS Server applications to get the location of a mobile device. You can also use the geolocation API to get the location from a standard web application, but this isn't nearly as accurate since it uses the IP address rather than GPS or cell tower triangulation.

This API has built-in security that requires explicit permission from the end user before this functionality can be used. Both mobile and web applications that use geolocation will prompt the user. This prompt will appear similar to the following screenshot:

Once you have the user's permission, using the API to retrieve location data is pretty straightforward.

The Geolocation.getCurrentPosition() method returns the current location of the mobile device. The Geolocation.watchPosition() method continually monitors the device location with a callback method being fired each time the position changes. So, if your application needs to be able to track the location...