Book Image

Mastering OpenLayers 3

By : Gábor Farkas
Book Image

Mastering OpenLayers 3

By: Gábor Farkas

Overview of this book

OpenLayers 3 allows you to create stunning web mapping and WebGIS applications. It uses modern, cutting edge browser technologies. It is written with Closure Library, enabling you to build browser-independent applications without painful debugging ceremonies, which even have some limited fallback options for older browsers. With this guide, you will be introduced to the world of advanced web mapping and WebGIS. First, you will be introduced to the advanced features and functionalities available in OpenLayers 3. Next, you will be taken through the key points of creating custom applications with OpenLayers 3. You will then learn how to create the web mapping application of yours (or your company's) dream with this open source, expense-free, yet very powerful library. We’ll also show you how to make amazing looking thematic maps and create great effects with canvas manipulation. By the end of this book, you will have a strong command of web mapping and will be well on your way to creating amazing applications using OpenLayers 3.
Table of Contents (17 chapters)
Mastering OpenLayers 3
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Index

Adding layers dynamically


Now that we have a basic layer tree, it's time to add some logic when adding layers. In this example, called ch03_addlayer, we will extend our code so far with some layer requesting and WMS metadata fetching capabilities. We will add every additional method to the object's prototype for the sake of clarity and performance.

Creating the interface

To keep things simple, we first hard code some forms in the HTML part. We will be able to add layers by filling out and submitting these forms. This will only need some event listeners in the JavaScript code. As these forms are quite verbose, we will only discuss the most important parts here. You can see the full code in the example's HTML file:

<div id="addwms" class="toggleable" style="display: none;">
    <form id="addwms_form" class="addlayer">
        [...]
                <td><input id="wmsurl" name="server" type="text"
                    required="required" value="http://demo.opengeo.org/geoserver...