Basics of XHTML-MP

Introduction:-

Challenges of Mobile Development :-

Mobile devices have several limitations

• Small screens

• Limited input capabilities

• Limited processor power and memory

• Limited bandwidth

These limitations have serious implications on the way one should design his/her mobile site.

XHTML MP (eXtensible HyperText Markup Language Mobile Profile) is the markup language defined in WAP 2.0 .The goal of XHTML Mobile Profile is to bring together the technologies for mobile Internet browsing and that for the World Wide Web

Main:-

Before Starting XHTML-MP we need to understand what is WAP

Short for the Wireless Application Protocol, a secure specification that allows users to access information instantly via handheld wireless devices such as mobile phones, pagers, two-way radios, smartphones and communicators.

WAP supports most wireless networks. These include CDPD, CDMA, GSM, PDC, PHS, TDMA, FLEX, ReFLEX, iDEN, TETRA, DECT, DataTAC, and Mobitex.

WAP is the standard created by the WAP Forum (now the Open Mobile Alliance [OMA]) that brings the World Wide Web to wireless devices. It specifies the protocol stack and application environment of mobile Internet browsing applications

The most up-to-date version of the WAP 1.x specification is WAP 1.2.1, which defines WML 1.3

WML files have the extension ".wml". The MIME type of WML is "text/vnd.wap.wml".

WML (Wireless Markup Language) is the first markup language standard for wireless devices. It is supported by all the major mobile phone manufacturers

WML 1.x is very similar to HTML. Both of them use tags and are written in plain text format. Some tags in WML 1.x are directly borrowed from HTML. If you have experience in using the HTML markup language, you should be able to learn WML 1.x quickly.

WAP 1.x is an earlier version of the WAP standard. The most current version is WAP 2.0. The markup language defined in WAP 2.0 is XHTML MP (XHTML Mobile Profile)

Some major WML features lost in XHTML MP:

1. XHTML MP does not support decks and cards

2. XHTML MP does not support timers

3. XHTML MP does not support events

4. XHTML MP does not support variables

5. XHTML MP does not support client-side scripting

6. XHTML MP does not support programmable softkeys

7. XHTML MP does not support the tag

8. XHTML MP does not support the format attribute for input fields

9. XHTML MP does not support posting of data with anchor links

XHTML MP is a subset of XHTML. The syntax rules of XHTML MP follow that of XHTML.

As mentioned before in this XHTML MP tutorial, XHTML is just a stricter and cleaner form of HTML. If you have already learned HTML, you can immediately start writing XHTML MP markup code by following the XHTML MP syntax rules below.

1. Tags must be closed properly

2. Tags and attributes must be in lowercase

3. Value of attributes must be enclosed within quotation marks

4. No attribute minimization is allowed

5. Tags must be nested properly

MIME types

The following three MIME types can be used for XHTML MP documents:

1. application/vnd.wap.xhtml+xml

2. application/xhtml+xml

3. text/html

The MIME type specified by the Open Mobile Alliance [OMA] for XHTML MP documents is "application/vnd.wap.xhtml+xml". This MIME type is required for some WAP browsers (for example, some Nokia Series 60 browsers) to display XHTML MP documents correctly.

Another choice is the "application/xhtml+xml" MIME type. It is the MIME type for XHTML Family document types.

The "text/html" MIME type is also a possible choice

File Extensions

The file extensions of static XHTML MP documents are ".xhtml", ".html" and ".htm" typically. You can use other file extensions you like, If you are going to use a server-side technology such as ASP, JSP, Perl, PHP or SSI (Server Side Includes) to add content to XHTML MP documents dynamically, you may need to change the file extension of your XHTML MP documents to that used by the server-side technology. For example, the typical file extension used by PHP is ".php", while that used by SSI is ".shtml".

DOCTYPE

Below is the DOCTYPE declaration for XHTML MP. You can simply copy and paste it into your XHTML MP files.

<!DOCTYPE html PUBLIC "-//WAPFORUM//DTD XHTML Mobile 1.0//EN" "http://www.wapforum.org/DTD/xhtml-mobile10.dtd">

The DOCTYPE declaration specifies the name of the DTD (Document Type Definition) and the URL to the DTD. The DTD contains information about the syntax of the markup language. It defines what elements and attributes can be used in the markup and the rules that they should be used.

Supported Modules

Modules included in XHTML-MP 1.2 are:

• Structure

• Texts

• Hypertext

• List

• Forms

• Basic Tables

• Image

• Object

• Metainformation

• Scripting

• Style Sheet

• Style Attribute

• Link

• Base

XHTML-MP 1.2 also includes partial support for:

• Presentation

• Intrinsic Events

• Legacy

Reference's:-

1. www.openmobilealliance.org

2. http://www.w3.org/TR/2001/REC-xhtml-modularization-20010410/

3. http://www.passani.it/gap/