Welcome to Instant HTML5 Geolocation How-to. This guide will help you make any web application aware of a user's location, quickly and easily. You will learn how to map a user's geographic location, integrate with popular mapping platforms, and track the user over time. In the process, you will create a simple application that generates a KML file containing both a path and points that you choose to save along that path (which can then be imported into Google Maps).
The iPhone changed the way we use the web. It was the first mobile device that included web browsing as a primary function. Suddenly, with mobile data and a phone like the iPhone, the web could be in your pocket, wherever you went. Through HTML5 and APIs, web applications could be truly context sensitive; they could know where you were, if you wanted them to, and react accordingly.
The Geolocation API is not part of HTML5, and is, instead, a JavaScript API standard. However, it sits alongside the evolving HTML5 specification as an important part of any modern web development toolkit.
Understanding the Geolocation API (Simple) discusses how the JavaScript Geolocation API works, when you should use it, and how it is implemented in different browsers and on different devices.
Setting up the application (Simple) explains how to configure and set up a sample application layout suitable for running a simple Geolocation-aware web application. Each step is explained in a way that will help you understand how your data will be stored so that you can scale your application when you're ready.
Getting the user's location (Intermidiate) illustrates how to detect Geolocation support in the user's web browser, use the API to obtain the user's coordinates, and handle any errors that might occur.
Displaying the user's location using the Google Maps API (Intermidiate) discusses how to display the coordinates obtained in the previous section in a visual way using Google Maps.
Displaying the user's location using a KML feed (Intermidiate) explains how to create the KML feed from coordinates you have saved in previous sections, and test it by importing it into Google Maps. KML feeds are supported by popular mapping applications such as Google Maps and Google Earth, as well as specialist GIS software.
Tracking and updating the user's location (Intermidiate) illustrates how to track the user and show his/her path, using simple web technologies. Sometimes, tracking the user's movements is important. Here we will use watchPosition() and clearPosition() to track the user's location over time, and change the maps that were created in the previous section.
You need to have access to a server or computer running Apache Web Server, MySQL, and PHP. You will also need a text editor, a recent version of a major web browser, and optionally, a web-capable mobile device with GPS support.
Instant HTML5 Geolocation How-to is for web developers who want to incorporate Geolocation technology into their applications. There is no need to know anything about Geolocation software or standards; each section has been designed to help you understand how the API works from beginning to end. However, this book assumes a general understanding of web technologies, and both JavaScript and jQuery in particular.
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