Using jQuery Mobile in Nokia Asha Web Apps
This article explains how to use jQuery Mobile to create highly portable Nokia Asha Web Apps.
The jQuery library has become the standard tool for web developers when building new web apps. Now that large part of web usage is coming from mobile devices its great to see that jQuery is providing tools to create web sites or applications that work with majority of phones and tablets.
The major benefit of using jQuery Mobile is that you can have a common application engine, and change the app appearance simply by dropping in a new theme. As a result you'll need to write less code to make your web app to work with several devices.
In this tutorial I'll show you how you can create simple (or complex) application easily with jQuery Mobile and how this application can be easily be developed for multiple platforms (Series 40 and Windows Phone). The project goal is to create Pocket (Read it Later) client. The application's name is Pouch and it is available along with full source code on Nokia Developer Projects.
Benefits of using jQuery Mobile over plain HTML
There are many benefits on using jQuery Mobile, to name a few:
- Themes - You can easily theme your application with jQuery Mobile ThemeRoller. There are also good 3rd party themes like Windows Phone theme as shown later in this article.
- Plugins - There are probably hundreds of jQuery Mobile plugins available. There are for example implementations for different components like date box and for different gestures like swipe to delete.
- Fast prototyping - Codiga have created an online editor which you can use to build prototypes really quickly - you can check demo version of this on jQuery Mobile site.
- Large community - There is large community behind jQuery Mobile and therefore new plugins, tutorials, themes are continuously being created.
We'll start by downloading and installing tools and libraries:
- Nokia Web Tools 2.0 - Great IDE and emulator for testing web apps on Nokia Asha devices
- jQuery Mobile - jQuery Mobile library (1.1.1 when writing this tutorial)
- Windows Phone Theme - Optional theme for Windows Phone
Create a new project
It really doesn't require much to use jQuery Mobile libraries in your Web Application. Set up a new project as usual:
- Start Nokia WDE
- Select File > New > Series 40 web app
- Select Basic Project
- Enter project name, version etc. information and click Finish
- New project is created
Next you can delete the s40-theme directory since the jQuery Mobile theme works well with Nokia Asha devices.
Add jQuery files to your project
Unzip your jQuery files and copy jquery.mobile-1.1.1.min.js and jquery-1.7.2.min.js to your project in folder js. Add the theme files to the css folder. Then add the following to your <head> tag:
<link rel="stylesheet" href="css/jquery.mobile-1.1.1.min.css" />
<link rel="stylesheet" href="css/jquery.mobile.theme-1.1.1.min.css" />
<link rel="stylesheet" href="css/jquery.mobile.structure-1.1.1.min.css" />
Main Application Structure
The following code snippet shows a simple application structure that you might define in index.html (the code is explained afterwards):
<div data-role="page" id="loginpage">
<div data-role="fieldcontain" class="ui-field-contain ui-body ui-br">
Enter Pocket credentials. Visit
<a href="http://getpocket.com">http://getpocket.com</a> if
you don't have account yet.
<label for="username" class="ui-input-text">Email:</label>
<input type="text" name="username" id="username" value="">
<label for="password" class="ui-input-text">Password:</label>
<input type="password" name="password" id="password" value="">
<button id="loginbutton" data-role="button">Login</button>
<div data-role="fieldcontain" class="ui-field-contain ui-body ui-br" style="text-align:right;">
© 2012 Tommi Laukkanen
</div><!-- /content -->
</div><!-- /page -->
<div data-role="page" id="menu">
<li><a id="addnewbutton">Add new</a></li>
<li><a id="allitemsbutton">All items</a></li>
<li><a id="logout-button" href="#loginpage" data-transition="slide">Logout</a></li>
</div> <!-- /menu page -->
<div data-role="page" id="itemlistpage">
<div data-role="header"><h1 style="white-space:normal;">Items</h1></div>
<ul id="itemlist" data-role="listview">
<button data-role="button" id="loadmorebutton">More</button>
<a data-role="button" href="#menu">Back</a>
</div> <!-- /item list page -->
<div data-role="page" id="newitempage">
<label for="newurl" class="ui-input-text">New URL:</label>
<input type="text" name="newurl" id="newurl" value="">
<button id="addbutton" data-role="button">Add</button>
<a id="backtolistbutton" data-role="button" href="#menu" data-transition="slide">Back</a>
</div> <!-- /item details page -->
First thing you'll notice is that application markup is divided into different pages. The data-role attribute are used to define semantics for the markup and in jQuery Mobile we can define which sections contain application pages, page content, page header, page footer and so on. You might have also noticed that I didn't use many class attributes, since jQuery Mobile uses the data attributes for styling different components.
Here are common data-role types that I have used in this sample application:
- page - Defines that section is contains components for one page - - Sample:
- content - Defines that section contains main content for the page - Sample:
- header - Header of page - Sample:
- footer - Footer of page - Sample:
- button - Button that does something - Sample:
- listview - List of items - Sample:
You can read more information about the data attributes and possibility of applying options to each data attribute from jQuery Mobile documentation: data-attribute reference
You can build basic navigation between your pages by binding the following script to your action:
// Switch to page newitempage with sliding transition
That is all you need to start using jQuery and jQuery Mobile in your web app. I don't go into details since great documentation for jQuery Mobile can be found at jquerymobile.com.
Switching to the Windows Phone theme
One of the greatest benefits of using jQuery Mobile is the theming support so that you'll only need to write the application logic once and then just change the theme if you'd like to run your application in different platforms and look more native.
Assuming you first downloaded the Windows Phone theme from here, then:
- Copy metro theme files to metro folder
- Change your application to use new theme:
And then you are ready! Then you'll need to use Windows Phone SDK and for example PhoneGap to compile your Web App to "native" Windows Phone application.
You can also review the Windows Phone theme in your Series 40 web app emulator:
jQuery Mobile is powerful framework but still lacks functionality which could be handy in Series 40 applications. In the future we, Series 40 community, could create a Series 40 theme to jQuery Mobile which would be as easy to plug-in as current Windows Phone theme.