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 – playing with zoom button and map copyrights

What we are customizing are the controls introduced in Chapter 9, Taking Control of Controls. It's time to try it: practicing things on your own will improve your comprehension. For this, we will reuse the OpenStreetMap example from Chapter 1, Getting Started with OpenLayers, and customize the position for zoom buttons and map copyrights.

  1. In the Sources panel, open the ol.css file and use the Format button to make it more readable as this file is a .css minified file on one line.
  2. Find the.ol-zoom class in the ol.css file.
  3. Replace the left : 0.5em; parameter with right : 0.5em; to make changes to zoom buttons.
  4. Now, it's time to change copyrights. So, like in the previous case, look for the CSS class, .ol-attribution:not(.ol-collapsed).
  5. Change the property background, rgba(255,255,255,0.8);, to rgba(255,0,0,.4);.
    Time for action – playing with zoom button and map copyrights

What just happened?

In the previous example, you played with HTML content. Here, the focus was to cover how you can change the style on the fly. We set the position of the zoom control to the top right and we also changed the background for attribution when you open the attributions collapsible block (credits to maps data and tiles) to red with an opacity change. We encourage you to perform more tests on your own to assimilate the way the panel works.

If you are a web designer working on the code or a web developer requiring to make some designs, we advise you to play a lot with this powerful panel. It can greatly speed up your development time when you master it. If you are always editing CSS in your browser, you should consider looking into the Workspace functionality we've already talked about.

The Console panel

The Chrome DevTools Console panel is where we'll spend most of our time. It acts as a powerful JavaScript command line, or interpreter, which means we can type in JavaScript code and execute it right away—no need to save or edit any files. We can also inspect values when we are stopped at a breakpoint in the Sources panel and want to inspect the context at this time.

Another thing that makes this panel so useful is that we can interact directly with the DOM (Document Object Model)—any HTML element on the web page, including any existing JavaScript code the page contains. So, this means we're able to interact with our OpenLayers map on the fly, issuing command and testing code to instantly see what works and what doesn't. As you can imagine, this saves a ton of time!

The Console panel

You can choose and type in the console on one line or multi-lines. To use multi-lines, type Shift + Enter to return without executing code.

When you need to discover the structure of an object, the Console panel is a very valuable tool, especially when you want to take a peek at JavaScript components. Assuming we are looking at a page that includes OpenLayers, we can quickly see all of OpenLayer's classes, functions, and so on. It is not a replacement for the API docs, but serves as a good, quick way to view such information.

The Resources panel

It looks like the screenshot that follows:

The Resources panel

With it, you have a classification of all types of resources. You get all resources depending on frames such as the images, CSS, and HTML files. It is a good way to know what your web page loads.

You also can see all persistent storage. Persistent storage are Web SQL, IndexedDB, Local Storage, Session Storage, and Cookies. Although they might not mean much to you, they provide features, not directly related to OpenLayers, can be useful as they are HTML5 features. We invite you to discover their purpose by visiting http://html5demos.com.

With this various storage, you can keep information for customizing users' experiences. For example, you can use them to customize the language for a web application, store the zoom level for a displayed map, and so on.

To complete and end this panel description, the last thing we need to inspect is the Application Cache. It is the most useful function for our book in Chapter 10, OpenLayers Goes Mobile. It helps you inspect the data cached using the MANIFEST file.

Timeline, Profiles, and the Audits panel

These three panels are not really useful for beginners. They target advanced developers mainly for performances purposes:

  • The Timeline panel enables you to record how the page content is processed to display the final image you see in the browser.
  • The Profile panel is mainly to evaluate computer resources consumed by the web page such as the memory consumed by JavaScript, the CSS selectors efficiency, and the overall memory allocation.
  • The Audits panel, like the name indicates, is an audit to give you information for improving performances at the network level or CSS levels for example.

If you want more information about these panels, visit the official documentation of Chrome DevTools at https://developers.google.com/chrome-developer-tools/.

Panel conclusion

Each panel serves a certain purpose and all of Google Chrome DevTools' panels are extremely useful, but throughout this book, we will be mainly focusing on the following panels:

  • The Console panel (Command-line JavaScript)
  • The Elements panel
  • The Sources panel
  • The Network panel

These four panels are the ones that we should use the most throughout this book. We can occasionally come back to the other panels, but we don't need to spend a whole lot of time with them. However, before we conclude this chapter, let's get a bit more familiar with the Console panel, since we will need it in most of our chapters.