Book Image

OpenLayers 3: Beginner's Guide

By : Thomas Gratier, Paul Spencer, Erik Hazzard
Book Image

OpenLayers 3: Beginner's Guide

By: Thomas Gratier, Paul Spencer, Erik Hazzard

Overview of this book

<p>This book is a practical, hands-on guide that provides you with all the information you need to get started with mapping using the OpenLayers 3 library.</p> <p>The book starts off by showing you how to create a simple map. Through the course of the book, we will review each component needed to make a map in OpenLayers 3, and you will end up with a full-fledged web map application. You will learn the key role of each OpenLayers 3 component in making a map, and important mapping principles such as projections and layers. You will create your own data files and connect to backend servers for mapping. A key part of this book will also be dedicated to building a mapping application for mobile devices and its specific components.</p>
Table of Contents (22 chapters)
OpenLayers 3 Beginner's Guide
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Time for action – finding your mouse position


Follow these steps to get started with the mouse position behavior:

  1. Reuse the usual HTML for the chapter by copying it in a new file.

  2. Now, edit the file to be sure that you create an HTML element with an ID myposition such as <div id="myposition"></div>.

  3. Declare a JavaScript variable that references the control:

    var mousePosition = new ol.control.MousePosition({
      coordinateFormat: ol.coordinate.createStringXY(2),
      projection: 'EPSG:4326',
      target: document.getElementById('myposition'),
      undefinedHTML: '&nbsp;'
    });
  4. Add the control to the map without forgetting that this operation is only available after you create the map:

    map.addControl(mousePosition);
  5. See the result in your browser and hover with your mouse the map.

  6. Go back in your HTML code and add the following code in your CSS file, assets/css/samples.css:

    #myposition > .ol-mouse-position {
      position: relative;
      margin-left: 20px;
      font-size: 30px;
    }
  7. Reload your page and you...