Book Image

Google Maps JavaScript API Cookbook

Book Image

Google Maps JavaScript API Cookbook

Overview of this book

Day by day, the use of location data is becoming more and more popular, and Google is one of the main game changers in this area. The Google Maps JavaScript API is one of the most functional and robust mapping APIs used among Geo developers. With Google Maps, you can build location-based apps, maps for mobile apps, visualize geospatial data, and customize your own maps.Google Maps JavaScript API Cookbook is a practical, hands-on guide that provides you with a number of clear, step-by-step recipes that will help you to unleash the capabilities of the Google Maps JavaScript API in conjunction with open source or commercial GIS servers and services through a number of practical examples of real world scenarios. This book begins by covering the essentials of including simple maps for Web and mobile, adding vector and raster layers, styling your own base maps, creating your own controls and responding to events, and including your own events.You will learn how to integrate open source or commercial GIS servers and services including ArcGIS Server, GeoServer, CartoDB, Fusion Tables, and Google Maps Engine with the Google Maps JavaScript API. You will also extend the Google Maps JavaScript API to push its capabilities to the limit with additional libraries and services including geometry, AdSense, geocoding, directions, and StreetView.This book covers everything you need to know about creating a web map or GIS applications using the Google Maps JavaScript API on multiple platforms.
Table of Contents (15 chapters)
Google Maps JavaScript API Cookbook
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Adding drag zoom to the map


Google Maps has a zoom control and the JavaScript API makes use of this control to offer a variety of options for programmers. It is a very useful and easy-to-use control. But there are other ways for zooming; for instance, by drawing an area of interest by dragging a box, so that the map zooms to that area.

This functionality does not exist in the standard Google Maps JavaScript API and any of its libraries; you have to code it. Or, you can make use of the utility libraries, developed by the good guys, at the following link:

https://code.google.com/p/google-maps-utility-library-v3/wiki/Libraries

One of their libraries, KeyDragZoom, is exactly for this zoom functionality, and we will use this library in this recipe.

Getting ready

You have to download the keydragzoom.js JavaScript source file from the following link (the latest release is 2.0.9 as of the time of writing this book) and place it in the same directory as our recipe source code:

http://google-maps-utility...