jQuery Mobile Deep Dive shows you how to create single page web apps that look and behave like native ones. We use JavaScript and open source libraries like jQuery, underscore, and backbone. And explore advanced topics like unit testing and performance optimization.
2. Google Maps
Full Throttle
• Learn the tips and tricks of the world’s
premier mapping app
• 21 September 2013
• Irvine, California USA
• http://bit.ly/156Mr5C
Saturday, September 7, 13
3. Want more? Follow me for more tutorials
and source code.
@therockncoder
Saturday, September 7, 13
4. Source code for my tutorials hosted on
GitHub @
https://github.com/Rockncoder
Saturday, September 7, 13
5. Before We Begin
• This class will move fast
• The source code is yours to keep
• The slides are available for download
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6. What Are We Going To
Do?
We are going to learn about jQuery Mobile by examining a
working application.We aren’t going to decompose each
line of code, instead we will examine each major area of
functionality.
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7. Coffee Coffee+
• jQuery Mobile
• Backbone
• Responsive Design
• Templates
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8. jQuery &
jQuery Mobile
• jQuery 1.9.x
• jQuery Mobile 1.3.2
• released on July 19th
• jQuery Mobile 1.4 which will support
jQuery 2.0, coming soon
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11. Globals are bad
• Try to use only one global variable
• Remember: JS objects can be modified at
runtime
• Use var app = app || {};
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12. Information Hiding
• JS lacks classes or other information
• One alternative is to wrap code in
anonymous functions
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16. JavaScript
• Define local variables
• Be careful with closures
• Accessing object properties and array items
is slower than variables
• Avoid for-in loops
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17. jQuery
• Don’t use .live()
• Use $.mobile.activePage
• Use preventDefault()
• Cache selector
• Know when not to use jQuery
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18. HTML
• Copy HTML collections into JS arrays
• Avoid accessing the DOM
• Use CSS classes not styles
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20. Templates
• Think of a template like a cookie cutter
• Fill it with data, and it produces HTML
• Templates can be used on the server or on
the client
• There are many templating engines
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22. Handlebars
• Create a template in a script tag
• Compile template in JS
• Render template with data
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23. Looping
• Handlebars has a built helper named, each,
for looping
• else can be used with each for when no
data is returned
• @index is the current loop index
• @key is the current object
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24. Conditional
• The if helper conditionally renders a block
• else is available for falsy values
• unless inverses the logic of the if
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25. Pre-compilation
• Precompile templates at application startup
for improved performance later
• Can also ship precompiled templates using
command line, node based tools
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26. Helpers
• Handlebars allows for the creation of JS
helper functions
• These handlers make it possible to extend
Handlebars functionality
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28. MV* Frameworks
• MV* Frameworks give an application
structure
• It is very easy to create spaghetti code in JS
• M = model
• V = controller
• * = something else, like routing
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29. MV* & jQuery Mobile
• jQuery Mobile and most frameworks don’t
get along well
• The main reason is routing. Both JQM and
MV* want to control the routes
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30. URL Routing
• URL are an invaluable part of the internet
• Users are use to sharing them
• They provide an easy mechanism to save
state in an otherwise stateless environment
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31. Routing
• It is better for the MV* to handle routing
• To stop JQM from handling routing
•26 <script type="text/javascript">
27 /* Prevent jQM from handling <a> clicks and # changes */
28 /* IMPORTANT: This must be hooked before loading jQM */
29 $(document).on("mobileinit", function () {
30 $.mobile.linkBindingEnabled = false;
31 $.mobile.hashListeningEnabled = false;
32 });
33 </script>
34 <script src="js/libs/jquery.mobile-1.3.2.min.js" type="text/javascript"></script>
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32. MV* Frameworks
• Angular.js, from Google
• Ember.js, based on SproutCore
• Backbone.js,
• and many more
• http://todomvc.com/
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33. Backbone.js
• A lightweight JS library which ads structure
to your client side code
• From the creator of Underscore
• Very small - 6.3k minified and gzipped
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34. Small and Fast
• Ember.js = 56k minified
• Angular.js = 81kb minified
• http://jsperf.com/angular-vs-knockout-vs-
ember/173
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35. The Nickel Tour
• Models
• Collections
• Views
• Routes
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36. The Happy Path
• Use extend to create a “class”
• Use built in methods like initialize
• Once the “class” is defined, use new to
instantiate an object
• “Classes” begins with upper case
• Objects begins with lower case
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39. Views
• Backbone.View.extend()
• Use the initialize method run handler code
which is executed once, like compiling
templates
• Use the render method to display the view
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42. Unit Testing
• Many unit testing frameworks are available
• QUnit, from the jQuery Team
• YUITest, fromYahoo
• Jasmine, from Pivotal Labs
• Mocha
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43. Unit Testing Tips
• Be sure to test logic
• Write tests before fixing bugs
• Never stop running test
• Refactor the tests, when your refactor the
code
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44. QUnit
• Probably the easiest one to learn
• Used to test all of the jQuery projects
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46. Custom Attributes
• A custom attribute is a non-standard
attribute added to a tag to convey some
information
• HTML has always supported custom
attributes
• HTML5 makes the support explicit instead
of implicit
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47. data-*
• The official way of creating custom
attributes is with data-
• Recommended is:
data-<company initials>-<attribute name>
• example: data-rnc-listingId
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48. getNamedItem()
• HTML, aka the DOM, includes the
getNamedItem() method
• Returns value of the attribute node with
the specified name
•/* set a click event on each row */
$(".listing").off().on("click", function () {
app.CurrentListing = this.attributes.getNamedItem("data-rnc-listingid").value;
});
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50. Meta tags
• meta tag is an element which is used to
provide structured metadata about a web
page
• They can be used to specify page
description, keywords, and instructions
• Always in the head section
• 5 defined attributes
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51. Meta Tag Attributes
• name, the name of the meta tag
• content, information for the reader
• http-equiv, character encoding, auto refresh
• scheme, specifies scheme to interpret
content (not support in HTML5)
• charset, added in HTML5
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53. Viewport
• A special meta tag used to provide
information about the device's display
•<meta name="viewport" content="width=device-
width,initial-scale=1,user-scalable=no,maximum-scale=1"/>
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54. Viewport Parameters
• width, the width of the viewport in pixels
• initial-scale, the zoom level when the page
loads
• maximum-scale, the max zoom level
• minimum-scale, the min zoom level
• user-scalable, if the user can change zoom
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55. Tips and Tricks
• There is no standard covering the viewport
• Apple probably has the best docs
• Type carefully, no error checking on
viewport
• Use the viewport standardize your app’s
screen size across different devices
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57. Media Queries
• The workhorse of responsive design
• A media query is a media type and at least
one expression that limits the style sheets'
scope
@media screen and (min-width: 480px) and (orientation:portrait)
{
}
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58. Media Query by the
Piece
• The media query begins with @media
• then a media type, like screen, all, print,
braille, etc
• You can add logical operators like: and, not,
and only
• There is also the comma separated list
which behaves like an or operator
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59. jQuery Mobile Features
• Grids, self sizing columns which dynamically
resize themselves when the size of the page
changes
• Tables, added with version 1.3.0
• Panels, ala Facebook, a panel, usually
options, reveals itself when an icon is
clicked
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61. Why?
Developers using other languages rarely think
of the size of their code. But client side
JavaScript is different. Minifying JavaScript can
dramatically reduce its size and radically reduce
page load time.
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62. How to Minify
• By Hand
• Using an app
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64. Using an App
• packer, http://dean.edwards.name/packer/
• Microsoft Ajax Minifier, http://
ajaxmin.codeplex.com/
• YUI Compressor, http://yui.github.io/
yuicompressor/
• Google Closure Compiler, http://closure-
compiler.appspot.com/home
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65. In Practice
• Hand minification is fraught with danger -
code is hard to read and grows increasingly
fragile
• Using a web site is good for an example but
not in practice, too much labor
• Usually done via a command line tool,
during build or on page request
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67. Icons
• Classic icon (Microsoft)
• Standardized
• Mobile icon (Apple)
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68. Splash Page
• An Apple thing
• The splash page is cached on the user’s
device
• When the icon is click on the home page,
splash page is shown while the app is
loaded
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