Book Image

Practical GIS

Book Image

Practical GIS

Overview of this book

The most commonly used GIS tools automate tasks that were historically done manually—compiling new maps by overlaying one on top of the other or physically cutting maps into pieces representing specific study areas, changing their projection, and getting meaningful results from the various layers by applying mathematical functions and operations. This book is an easy-to-follow guide to use the most matured open source GIS tools for these tasks. We’ll start by setting up the environment for the tools we use in the book. Then you will learn how to work with QGIS in order to generate useful spatial data. You will get to know the basics of queries, data management, and geoprocessing. After that, you will start to practice your knowledge on real-world examples. We will solve various types of geospatial analyses with various methods. We will start with basic GIS problems by imitating the work of an enthusiastic real estate agent, and continue with more advanced, but typical tasks by solving a decision problem. Finally, you will find out how to publish your data (and results) on the web. We will publish our data with QGIS Server and GeoServer, and create a basic web map with the API of the lightweight Leaflet web mapping library.
Table of Contents (22 chapters)
Title Page
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Dedication
Preface
14
Appendix

Creating web maps with Leaflet


Now we have everything in place except our maps. To create interactive maps, we can use external web mapping libraries written in JavaScript. One such library is Leaflet, which is perfectly capable of creating simple interactive maps. Leaflet has a simple and intuitive API, which is very easy to use. All we need is the library's code base and stylesheet loaded in our HTML document. Let's include Leaflet in our web page:

  1. Download the stable version of Leaflet from http://leafletjs.com/download.html.
  2. Extract the files in the downloaded archive in the web server's root folder. Optionally, create a new folder for the files to have a well-organized structure.
  3. Edit the map.html file with a code or text editor.
  4. Include Leaflet's code base (leaflet.js) with a <script> element using its relative path from the root folder in the HTML document's <head> section:
        <script src="leaflet/leaflet.js" type="text/javascript">
        </script>
  1. Include...