Mobile Web Markup Language

Mobile Web Markup Language

M.C. Juan Carlos Olivares Rojas

Department of Computer and SystemInstituto Tecnológico de Morelia

[email protected] lat, -101.1848 long

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Outline• Introduction

• WML

• XHTML-MP

• Conclusions

Objectives of the Session• Discuss the relationship between XHTML,

XHTML Basic, XHTML-MP.

• Do some practical work in XHTML MP – developing a WAP 2.0 mobile website.

• Examine Cascading Style Sheets (CSS) and how they can be used for mobile website design.

Introduction• The use of mobile devices has increased

tremendously in recent years (e.g., cell phones, PDAs, and other handheld devices).

• Mobile devices are different from traditional Web browsers:– Lower bandwidth– Lower memory– Limited display area– Limited input devices

• Therefore, protocols and languages that are specific for wireless applications have been designed.

Introduction• Wireless Application Protocol (WAP 1.0) was

the first Internet service for mobile devices. WAP pages were written in WML (Wireless Mark-up Language).

• WAP 2.0 is the Mobile Web with added ‘colour’ and enhanced media capabilities – more converged with Web development for PCs.

• WAP 2.0 Web pages are generally designed in XHTML MP.

Markup Language Convergence

1998 1999 2000 2001 2002

WAP

HTML

XML

HDML

WML XHTML Basic + WML

HTML 3.2

C-HTML

HTML 4.0

XHTML 1.0

XHTML BasicXML 1.0

WAP 2.x

WAP 1.x

i-mode

WAP Architecture

Data General

WAP Gateway

Web Server

WAP Tools• Nokia WAP SDK

• WinWAP

• MobileDev

• Nokia WML Studio for Macromedia Dreamweaver

• Ericsson WAPIDE

• IBM WAPSody

A Simple WML File

• A Simple WML file

<?xml version='1.0'?><!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN" "http://www.wapforum.org/DTD/wml_1.1.xml"><wml><card id="First_Card" title="First Card"><p>Welcome to WML!</p></card></wml>

Standard header for WML 1.1 files

BUSI 0063 Handout 7 - Wireless Application Development 11

A WML Example with Cards<?xml version='1.0'?><!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN" "http://www.wapforum.org/DTD/wml_1.1.xml"> <wml> <card id="Login" title="Login"> <do type="accept" label="Password"> <go href="#Password"/> </do> <p> UserName: <select name="name" title="Name:"> <option value="Charlene">Charlene</option> <option value="Gillian">Gillian</option> <option value="Rosanne">Rosanne</option> <option value="Race">Race</option> </select> </p> </card>

Login Card - the first card here

Select menu – a common control in WML

Go to Password card when user selects it

(continued from previous slide)

<card id="Password" title="Password:"> <do type="accept" label="Results"> <go href="#Results"/> </do> <p> Password: <input type="text" name="password"/> </p> </card>

<card id="Results" title="Results:"> <p> You entered:<br/> Name: $(name)<br/> Password: $(password)<br/> </p> </card></wml>

The Password card

The Results card


WMLScript• Similar to JavaScript in HTML

• Used to add client-side logic to WAP pages

• Can be used for form validation and other client-side functions.

• WMLScripts are NOT embedded in WML pages; they are stored as separate files.


A WMLScript Example<?xml version='1.0'?><!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN" "http://www.wapforum.org/DTD/wml_1.1.xml"> <wml> <card id="Phone" title="Phone:"> <do type="accept" label="Results"> <go href="example4.wmls#validate($(Phone))"/> </do> <p> Enter phone: <input type="text" name="Phone"/> </p> </card>

<card id="Results" title="Results:"> <p> You entered:<br/> Phone: $(Phone)<br/> </p> </card></wml>

http://147.8.210.143/wireless/example4.wml


A WMLScript Example

extern function validate(Phone){ if (String.length(Phone) != 8) { WMLBrowser.setVar("Phone", "Error: Phone not correct."); } WMLBrowser.go("example4.wml#Results");} http://147.8.210.143/wireless/example4.wmls

What is XHTML?• Developing XHTML is very much like developing using

HTML. The elements (tags) and attributes are almost identical.

• XHTML is an intersection of HTML and XML – a reformulation of HTML as an application of XML.

• Pages written in XHTML work well in most browsers.

• XHTML is stricter than HTML. All tags, including empty elements, must be closed and in lower case.

• It is defined by W3C

XHTML Basic• XHTML Basic is essentially a cut-down version of

XHTML, suitable for devices with limited processing and display capabilities (such as handhelds).

• It still looks like a lot like HTML, but without many features that are hard to support on mobile devices: frames, nested tables, internal style sheets (CSS), complex forms and scripting.

• XHTML Basic was again defined by W3C. See http://www.w3.org/TR/xhtml-basic for background.

http://www.w3.org/TR/xhtml-basic

XHTML Basic – Modules and Elements

Note: The Elements look a lot like regular HTML and behave in a very similar way

XHTML Mobile Profile• The WAP Forum (now OMA) added some

features to XHTML Basic in order to rectify some of its limitations, thus creating XHTML Mobile Profile (MP).

• XHTML MP extends XHTML Basic to bring extra functionality to developers, including more display elements and internal style sheets (CSS).

• XHTML MP is a strict subset of XHTML.

Rules for XHTML Documents• All tag and attribute names should be lowercase

• "Empty" tags must have an extra slash at the end

• Never leave out an end tag. Usually save files with the extension ".xhtml“

• Tags must be correctly ‘nested’ (e.g. <div><em>emboldened text</em></div>)

Font Style Code Example

<?xml version="1.0"?><!DOCTYPE html PUBLIC "-//WAPFORUM//DTD XHTML Mobile 1.0//EN"

"http://www.wapforum.org/DTD/xhtml-mobile10.dtd"><html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Font Style</title>

<link rel="stylesheet" href="style.css" type="text/css" /> </head> <body> <div> <b>Bold</b><br/> <i>Italic</i><br/> <b><i>Bold italic</i></b><br/> <small>Small</small><br/> <big>Big</big><br/> <em>Emphasis</em><br/>

<strong>Strong</strong><h1>h1</h1><h2>h2</h2><h3>h3</h3>

</div> </body></html>

Lists Code Example<?xml version="1.0"?> <!DOCTYPE html PUBLIC "-//WAPFORUM//DTD XHTML Mobile 1.0//EN" "http://www.wapforum.org/DTD/xhtml-mobile10.dtd">

<html xmlns="http://www.w3.org/1999/xhtml"> <head>

<title>Unnumbered Lists</title> </head>

<body> <div><em>Unnumbered List:</em></div> <ul> <li>First Item</li> <li>Second Item</li> <li>Third Item</li> <li>And so on...</li> </ul>

</body> </html>

Tables Code Example• XHTML MP provides support for use of

tables<head>

<title>An XHTML MP Table</title></head>

<body><table>

<tr> <td>Item 1</td> <td>Item 2</td> </tr>

<tr>

<td>Item 3</td>

<td>Item 4</td> </tr>

</table> </body>

A Sample XHTML-MP Page<?xml version="1.0"?><!DOCTYPE html PUBLIC "-//OPENWAVE//DTD XHTML Mobile 1.0//EN" "http://www.openwave.com/DTD/xhtml-mobile10.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en"> <head> <title>XHTML Samples</title> </head> <body> <ol> <li><a accesskey="1" href="inbox.html">Check emails</a></li> <li><a accesskey="2" href="movies.html">Movies Info</a></li> <li><a accesskey="3" href="about.html">About</a></li> </ol> </body></html>

Quick access key

A Sample XHTML-MP Page<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE html PUBLIC "-//OPENWAVE//DTD XHTML Mobile 1.0//EN" "http://www.openwave.com/dtd/xhtml-mobile10.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en"> <head> <title> About this Site </title> </head> <body> <p> This is a test site. </p> <hr/> </body></html>

Nokia Code Example

<?xml version="1.0" encoding="utf-8"?><!DOCTYPE html PUBLIC "-//WAPFORUM//DTD XHTML Mobile 1.0//EN" "http://www.wapforum.org/DTD/xhtml-mobile10.dtd" >

<html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>XHTML Mobile Profile Document</title>  <link rel="stylesheet" href="style.css" type="text/css"/>  </head> <body> <h1> Heading </h1> <p> Body </p> </body></html>

Another Nokia Code Example

<?xml version="1.0"?>

<!DOCTYPE html PUBLIC "-//WAPFORUM//DTD XHTML Mobile 1.0//EN"

"http://www.wapforum.org/DTD/xhtml-mobile10.dtd" >

<html xmlns="http://www.w3.org/1999/xhtml">



<head>

<title>Stale News Portal</title>



<link rel="stylesheet" href="style.css" type="text/css"/>

<style type="text/css">

</style>

</head>

Another Nokia Code Example



<body>



<h2>Stale News Portal</h2>

<p>

<img src="icons/news.gif" alt="new" />

Categories:

</p>

<ul>

<li><a href="entertainment.xhtml">Entertainment</a></li>

<li><a href="business.xhtml">Business</a></li>

<li><a href="world.xhtml">World</a></li>

<li><a href="weather.xhtml">Weather</a></li>

<li><a href="updates.xhtml">SMS Alerts</a></li>

</ul>



<p class="small"><br/>

<a href="about.xhtml">About Stale News Portal</a>

</p>

</body>

</html>

Cascading Style Sheets (CSS)• XHTML supports CSS.

• CSS allows you to establish a consistent design and formatting across all pages of a site.

• With CSS, if you want to change the style or formatting of a page, you just have to change the CSS, not each page element individually

Cascading Style Sheets• XHTML Basic only supports CSS through

external links but XHTML-MP allows internal CSS as well.

• Use caution with external CSS. In theory, external CSS allows you to have one CSS that applies to your entire site while reducing the amount of downloading the user has to do. In practice, many browsers do not cache the CSS and thus download it again for each page the user visits. Further, when the CSS is downloaded, the already-displayed XHTML content jumps around to render the new styling.

CSS code example

Save the following as "style.css" in the same folder:

body { background-color: #efefdd; font-family: Arial, Verdana, Helvetica; font-size: 10pt; color: #000044;}

div { font-family: Arial, Verdana, Helvetica; font-size: 10pt; color: #000044;}

hr { color:#006600;}

h1 { font-family: Verdana, Arial, Helvetica; font-size: 14pt; color: #000000;}h2 { font-family: Verdana, Arial, Helvetica; font-size: 12pt; color: #000000;}h3 { font-family: Verdana, Arial, Helvetica; font-size: 10pt;font-weight:bold;

color: #00000;}

a { color: #1144aa; text-decoration: none;}a:hover { text-decoration: underline;}a:visited { color: #4466cc;}

Mobile Design Good Practices• Limit categories to 5

• Limit links to 10

• No more than 5 levels deep

• At least one content item per category

• Prioritize links by activity or popularity

Mobile Design Good Practices• Ensuring the use of the correct character encoding and

doctype makes sure that the page renders as expected.

• Avoid tables for layout

• Use accesskeys in the primary navigation

• Use document styles, not external styles – insert styles into the <head> of a document.

• Use few or no forms. If you have to use forms, keep required information as little as possible.

• Make telephone number links

Guidelines for Mobile Content• Keep it simple!

– WAP browsers have limited capabilities

• Keep images small– Use smallest palette possible (256 web-safe palette):

• Scale images to fit the device before delivery:– Keep the file size of your images as small as possible

• Always include alt text.– The browser may not display images, or images may be

corrupted by communications errors.

Guidelines for Mobile Content• Keep your pages small.

• Wireless bandwidth is scarce: big pages download slowly.

• Keep images small and suitable for low resolution.

• Test, test, test.

• Because WML & XHTML-MP are relatively new, test compatibility with different browsers!

Bad vs Good

References• Robison, D. and Pagna, J., (2008) , Wap 2.0

Mobile Web: XHTML Mobile Profile.

• Kantor, P. (2006), XHTML, Desert Code 2006.

• Skelton, G., Excell, P., Robison, D. and Taj, I. (2008) XHTML Basic and XHTML-MP.

• Ingram, M. (2008) Mobile Devices: Driving Standards for a “New” Web.

¿Preguntas?