Table of Contents for
OpenLayers 3 : Beginner's Guide

Version ebook / Retour

Cover image for bash Cookbook, 2nd Edition OpenLayers 3 : Beginner's Guide by Erik Hazzard Published by Packt Publishing, 2015
  1. Cover
  2. Table of Contents
  3. OpenLayers 3 Beginner's Guide
  4. OpenLayers 3 Beginner's Guide
  5. Credits
  6. About the Authors
  7. About the Reviewers
  8. www.PacktPub.com
  9. Preface
  10. What you need for this book
  11. Who this book is for
  12. Sections
  13. Time for action – heading
  14. Conventions
  15. Reader feedback
  16. Customer support
  17. 1. Getting Started with OpenLayers
  18. Advantages of using OpenLayers
  19. What, technically, is OpenLayers?
  20. Anatomy of a web mapping application
  21. Connecting to Google, Bing Maps, and other mapping APIs
  22. Time for action – downloading OpenLayers
  23. Time for action – creating your first map
  24. Where to go for help
  25. OpenLayers issues
  26. OpenLayers source code repository
  27. Getting live news from RSS and social networks
  28. Summary
  29. 2. Key Concepts in OpenLayers
  30. Time for action – creating a map
  31. Time for action – using the JavaScript console
  32. Time for action – overlaying information
  33. OpenLayers' super classes
  34. Key-Value Observing with the Object class
  35. Time for action – using bindTo
  36. Working with collections
  37. Summary
  38. 3. Charting the Map Class
  39. Time for action – creating a map
  40. Map renderers
  41. Time for action – rendering a masterpiece
  42. Map properties
  43. Time for action – target practice
  44. Map methods
  45. Time for action – creating animated maps
  46. Events
  47. Views
  48. Time for action – linking two views
  49. Summary
  50. 4. Interacting with Raster Data Source
  51. Layers in OpenLayers 3
  52. Common operations on layers
  53. Time for action – changing layer properties
  54. Tiled versus untiled layers
  55. Types of raster sources
  56. Tiled images' layers and their sources
  57. Time for action – creating a Stamen layer
  58. Time for action – creating a Bing Maps layer
  59. Time for action – creating tiles and adding Zoomify layer
  60. Image layers and their sources
  61. Using Spherical Mercator raster data with other layers
  62. Time For action – playing with various sources and layers together
  63. Time For action – applying Zoomify sample knowledge to a single raw image
  64. Summary
  65. 5. Using Vector Layers
  66. Time for action – creating a vector layer
  67. How the vector layer works
  68. The vector layer class
  69. Vector sources
  70. Time for action – using the cluster source
  71. Time for action – creating a loader function
  72. Time for action – working with the TileVector source
  73. Time for action – a drag and drop viewer for vector files
  74. Features and geometries
  75. Time for action – geometries in action
  76. Time for action – interacting with features
  77. Summary
  78. 6. Styling Vector Layers
  79. Time for action – basic styling
  80. The style class
  81. Time for action – using the icon style
  82. Have a go hero – using the circle style
  83. Multiple styles
  84. Time for action – using multiple styles
  85. Style functions
  86. Time for action – using properties to style features
  87. Interactive styles
  88. Time for action – creating interactive styles
  89. Summary
  90. 7. Wrapping Our Heads Around Projections
  91. Time for action – using different projection codes
  92. Time for action – determining coordinates
  93. OpenLayers projection class
  94. Transforming coordinates
  95. Time for action – coordinate transforms
  96. Time for action – setting up Proj4js.org
  97. Time for action – reprojecting extent
  98. Time for action – using custom projection with WMS sources
  99. Time for action – reprojecting geometries in vector layers
  100. Summary
  101. 8. Interacting with Your Map
  102. Time for action – converting your local or national authorities data into web mapping formats
  103. Time for action – testing the use cases for ol.interaction.Select
  104. Time for action – more options with ol.interaction.Select
  105. Introducing methods to get information from your map
  106. Time for action – understanding the forEachFeatureAtPixel method
  107. Time for action – understanding the getGetFeatureInfoUrl method
  108. Adding a pop-up on your map
  109. Time for action – introducing ol.Overlay with a static example
  110. Time for action – using ol.Overlay dynamically with layers information
  111. Time for action – using ol.interaction.Draw to share new information on the Web
  112. Time for action – using ol.interaction.Modify to update drawing
  113. Understanding interactions and their architecture
  114. Time for action – configuring default interactions
  115. Discovering the other interactions
  116. Time for action – using ol.interaction.DragRotateAndZoom
  117. Time for action – making rectangle export to GeoJSON with ol.interaction.DragBox
  118. Summary
  119. 9. Taking Control of Controls
  120. Adding controls to your map
  121. Time for action – starting with the default controls
  122. Controls overview
  123. Time for action – changing the default attribution styles
  124. Time for action – finding your mouse position
  125. Time for action – configuring ZoomToExtent and manipulate controls
  126. Creating a custom control
  127. Time for action – extending ol.control.Control to make your own control
  128. Summary
  129. 10. OpenLayers Goes Mobile
  130. Using a web server
  131. Time for action – go mobile!
  132. The Geolocation class
  133. Time for action – location, location, location
  134. The DeviceOrientation class
  135. Time for action – a sense of direction
  136. Debugging mobile web applications
  137. Debugging on iOS
  138. Debugging on Android
  139. Going offline
  140. Time for action – MANIFEST destiny
  141. Going native with web applications
  142. Time for action – track me
  143. Summary
  144. 11. Creating Web Map Apps
  145. Using geospatial data from Flickr
  146. Time for action – getting Flickr data
  147. A simple application
  148. Time for Action – adding data to your map
  149. Styling the features
  150. Time for action – creating a style function
  151. Creating a thumbnail style
  152. Time for action – switching to JSON data
  153. Time for action – creating a thumbnail style
  154. Turning our example into an application
  155. Time for action – adding the select interaction
  156. Time for action – handling selection events
  157. Time for action – displaying photo information
  158. Using real time data
  159. Time for action – getting dynamic data
  160. Wrapping up the application
  161. Time for action – adding dynamic tags to your map
  162. Deploying an application
  163. Creating custom builds
  164. Creating a combined build
  165. Time for action – creating a combined build
  166. Creating a separate build
  167. Time for action – creating a separate build
  168. Summary
  169. A. Object-oriented Programming – Introduction and Concepts
  170. Going further
  171. B. More details on Closure Tools and Code Optimization Techniques
  172. Introducing Closure Library, yet another JavaScript library
  173. Time for action – first steps with Closure Library
  174. Making custom build for optimizing performance
  175. Time for action – playing with Closure Compiler
  176. Applying your knowledge to the OpenLayers case
  177. Time for action - running official examples with the internal OpenLayers toolkit
  178. Time for action - building your custom OpenLayers library
  179. Syntax and styles
  180. Time for action – using Closure Linter to fix JavaScript
  181. Summary
  182. C. Squashing Bugs with Web Debuggers
  183. Time for action – opening Chrome Developer Tools
  184. Explaining Chrome Developer debugging controls
  185. Time for action – using DOM manipulation with OpenStreetMap map images
  186. Time for action – using breakpoints to explore your code
  187. Time for action – playing with zoom button and map copyrights
  188. Using the Console panel
  189. Time for action – executing code in the Console
  190. Time for action – creating object literals
  191. Time for action – interacting with a map
  192. Improving Chrome and Developer Tools with extensions
  193. Debugging in other browsers
  194. Summary
  195. D. Pop Quiz Answers
  196. Chapter 5, Using Vector Layers
  197. Chapter 7, Wrapping Our Heads Around Projections
  198. Chapter 8, Interacting with Your Map
  199. Chapter 9, Taking Control of Controls
  200. Chapter 10, OpenLayers Goes Mobile
  201. Appendix B, More details on Closure Tools and Code Optimization Techniques
  202. Appendix C, Squashing Bugs with Web Debuggers
  203. Index

Time for action - running official examples with the internal OpenLayers toolkit

We will inspect reusing the workflow for developing the OpenLayers core library to run the official examples. For this purpose, start with the following step:

  1. Download the project code in your command line:
    git clone https://github.com/openlayers/ol3.git
cd ol3
git checkout v3.0.0
  2. Install Node and Python additional libraries with:
    npm install
sudo pip install -r requirements.txt
  3. Run from the command line, on Windows, build.cmd checkdeps or ./build.py checkdeps on Linux / Mac OSX. It will return if dependencies are solved to proceed to the next step.
  4. To retrieve Closure Compiler and use the automatic configuration from the OpenLayers project, launch on Microsoft Windows:
    build.cmd
build.cmd host-examples
build.cmd serve
  5. On Linux / Mac OSX:
    ./build.py
./build.py host-examples
./build.py serve

    Note

    You may need an offline API, if for example, you're working in public transportation or without a network connection. To generate it, execute the ./build.py apidoc or build.cmd apidoc. Then, open it with http://localhost:3000/build/hosted/HEAD/apidoc/. You can also get it directly from the v3.0.0.zip file, downloaded from Chapter 1, Getting Started with OpenLayers.

  6. Now, open your browser at http://localhost:3000/examples/ and open Google Chrome Developers Tools. You will see the examples like the one you get on the official website that follows:
    Time for action - running official examples with the internal OpenLayers toolkit
  7. Explore the examples and watch for the Elements, Network, and Sources panel, in particular the JavaScript calls.
  8. Then, navigate to http://localhost:3000/build/hosted/HEAD/examples/attributions.html.
  9. Try to add the URL of the examples ?mode=whitespace or ?mode=simple, or ?mode=raw.

What just happened?

We serve files on a small web server. In the first case, the loader.js file retrieves the dependencies and adds for each required files the script tag with the src attribute. In the second case, we chose to open the hosted files, the ones you get when you browse the official website, http://openlayers.org.

In the second case, depending on the provided values for the mode parameter, we will load different files for the OpenLayers 3 library:

  • Raw: This loads each input via its own <script> tag. This does not run the Compiler, so no checks are performed.
  • Whitespace: This loads all of the JavaScript code concatenated together with all white space and comments removed.
  • Simple: This loads the JavaScript as compiled with SIMPLE_OPTIMIZATIONS enabled. Without an option in the URL, this loads the JavaScript as compiled with ADVANCED_OPTIMIZATIONS enabled.

Hey! These options look familiar, where did we see them?

Remember that we had mentioned to you that OpenLayers tools are using Closure Compiler. Let's see how OpenLayers takes benefits from it.

OpenLayers 3 default build tool advantages

When you changed examples with the raw mode, you may have noticed (in particular by filtering the script in the Network panel) that the loaded files number greatly differs from the URL without it. What can make this difference? Let's see some practical uses to understand.

Removing the unused code feature

We waited until now to review the removal of the unused code feature related to Google Closure Compiler.

As we already said, when you switch between examples, you load different files. How does it work?

Open your browser Network panel. Open the URL for one of the official examples and add ?mode=raw.

Then, in the console, type console.log(paths.length);.

Just compare the length between the examples. If your example in the URL is animation.html, inspect also the animation-require.js files, you will see that there are some lines beginning with goog.require('...'). The loader gets the name from the file via loader?id=examplename, and with the goog.require indications from examplename-require.js, Closure Compiler generates the list of files to load for the example.

When Compiler does not find the required goog.require statements, it excludes the files and the resulting build file is smaller. On mobile applications, it is invaluable. Just be careful to not break your application, for example, if you forget to add a statement.

Making your custom build

When you run ./build.py or build.cmd, you have something such as 2014-12-10 18:41:23,358 build/ol.js: node tasks/build.js config/ol.json build/ol.js. We will reuse the beginning command to compile the ol.js file again and play with the Closure Compiler builder included in the OpenLayers 3 toolkit. The ol.json file is used to provide parameters to Closure Compiler to make the build and ol.js is the output result.

To build, you have two choices:

  • Build the code to make it work with a separate .js lightened build
  • Build the code by including the OpenLayers library code, together with the script file

At the moment, you have a shared JSON file for all examples in config/examples-all.json. We will reuse it.