How To Build WAP-Ready Website.pdf

hands on

WAP-ready Web site

The latest Internet buzzword is WAP. Simon Bisson embarks on a new

series showing you how to get your Web pages on to people’s mobiles

ith millions of mobile phones already

in use, it’s no wonder that over £22

billion pounds was raised by the recent auction

of third generation mobile phone licences.

Promising 2Mbps connections, the next

generation of mobile phones is going to change

the way we see the Internet.

You don’t need to wait that long to see the

mobile Internet, as the first few WAP (Wireless

Applications Protocol) phones have started to

appear – phones that will at least enable you to

use some Web services wherever you are...

Creating WAP pages

So how can you create your own pages for WAP

phones? WAP is an important step on the route

to an always-accessible Internet applications

framework, enabling mobile phones to access

simple text and form-based Web applications.

Working with WAP pages is similar to working

with traditional Web architectures. A WAP

Gateway acts as an interface between the TCP/IP

world and the mobile phone, translating

information and passing it to and from the

phone. One thing to remember with WAP is that

you don’t use HTML, which is designed for use

on large screens. Instead, WAP uses a mark up

language of its own: the Wireless Mark-up

Language (WML). You’ll find all the details of

WAP 1.2, the current version of the WAP

standard, on the WAP Forum’s excellent Web site:

www.wapforum.org .

If you’re used to working with HTML, you’ll

find some aspects of WML familiar, while others

The Nokia WAP Toolkit is one of the most popular

WAP development environments. You can use it to

edit and test your WML code. It’ll even simulate a

WAP Gateway to make your applications run correctly.

It’s a good idea to use as many different WAP

development toolkits as possible – as every phone

behaves differently. Here we’re using our test file in a

simulated Motorola P7389.

are very different indeed. WML is defined as an

XML DTD (Document Type Definition), so it

requires more care in implementation than a

piece of HTML code. You will need to be sure that

the tags you’re using are correctly terminated

otherwise a WML browser will fail to parse and

display your page.

You’ll find micro-browsers generally limited –

and thanks to their integration with the standard

mobile phone handset, also difficult to design

for. What works in a Nokia phone can’t be

guaranteed to work in a Motorola or Ericsson.

A deck of cards

To make things easier, every WML page is divided

into ‘cards’, each of which is displayed as a

separate entity by the WML browser. This deck of

cards approach requires you to explicitly add

navigation instructions to your cards, so that

users will be able to access the information you’re

delivering to their phones. You can use <a href>

style links, which aren’t understood by every

phone, or by using WML’s <do> and <go> tags,

which work with a phone’s built-in menu system.

WAP browsers

The WML browsers in WAP phones are known as

‘micro browsers’, and you’ll need to be careful

how you design content that will be delivered by

WAP. The first generation of WAP phones, like

the Nokia 7110 or the Motorola P7389, have

displays can only show 3 or 4 lines of text at a

time. You must take this account when you’re

designing WML pages.

THE NEXT GENERATION

iMode – Japan shows the way to the future

In Japan the mobile Internet is using HTML and colour displays...

hile the western world has standardised

WAP and WML as the key technologies for

mobile Internet services, they are limited by the

low speeds of the current GSM data network. In

these days of ADSL and cable modems, 9,600 bits

per second is somewhat slow...

Over the next few months the main GSM

network operators in the UK will be rolling out the

General Packet Radio Service (GPRS) services.

The GPRS is a different way of delivering mobile

data, as it is equivalent to an always-on ISDN

connection. The next generation of the WAP

standard, WAP 1.2, is likely to add new services

designed to support these higher bandwidth

connections. But what type of applications will

we see?

One pointer could be NTT DoCoMo’s wireless

Internet service iMode. This is a 22Kbps packet

radio service running in Japan’s main cities. Its low

prices have attracted a lot of subscribers, and it

uses a compact version of HTML to deliver

applications to phones.

C-HTML is easy to use and it’s very easy to

convert existing Web sites to run in iMode phones.

With most of the main Japanese consumer

electronics companies producing iMode phones,

they’re becoming cheaper and more sophisticated

– with the latest offering colour displays. Games

and chat are the most popular services on iMode,

with some phones downloading new Tamagotchi

or Pokémon-style characters for a small fee. You

can also shop on-line, or access your bank details.

Next year will see the British Isles’ first 3G

trials in the Isle of Man. BT Cellnet has partnered

with NTT DoCoMo to see how the iMode

experience can be brought to the next generation

of mobile phones.

You can find out more about iMode at

www.nttdocomo.com/.

164

PC Plus August 2000

How to build a

web workshop

Every card has an ID and a name. The ID is

used to handle navigation between the cards in

the deck. The simple deck shown below has a

single card, which will display a line of text in a

phone’s screen.

<option value=”Goodbye”> Goodbye

</option>

</select>

CODE CORNER

Your first WAP

page

WML won’t be too unfamiliar to

anyone used to HTML. Just

remember, it’s a lot stricter

<?xml version=”1.0”?>

<!DOCTYPE wml PUBLIC “

//WAPFORUM//DTD WML 1.1//EN”

“http://www.wapforum.org/DTD/wml_

.1.xml”>

<wml>

<card

id=”card1”title=”PCplus”>

<do

type=”accept”label=”Next”>

</do>

<p>

This is a test WML deck

for PC Plus.

</p>

</card>

<card id=”card2” title=”Pick

List”>

<do

type=”accept”label=”Next”>

</do>

<p>

Please choose a word:

<br/>

<select name=”word”

value=”Hello”title=”Word”>

<option

value=”Hello”> Hello</option>

<option

value=”Goodbye”> Goodbye</option>

</select>

</p>

</card>

<card id=”card3”

title=”Name”>

<do type=”accept”

label=”Next”>

</do>

<p>

Please enter your name:

<br/>

<input type=”text”

format=”*M” name=”NAME”

title=”Name:”/>

</p>

</card>

<card id=”card4”

title=”Display”>

<p>

$word

$NAME

One difference from HTML is that you can

access the resulting value and display it in the

rest of the cards of a deck, before submitting back

to a Web server for processing just like a standard

form. The ‘name’ of a select block is used to hold

the resulting value, and it can be displayed by

prefixing it with a $. In our example, card 4

displays both the values of the select block and

the input statement.

Select blocks are the best way of creating

interactive WML applications. You can use them

to provide a WAP site’s users with pre-configured

choices, rather than expecting them to use the

phone to type in values.

One of the difficulties with a phone’s simple

keyboard is that is can take up to 4 key presses

just to enter a letter. If a free form input is

needed, you can use the input tag to control a

user’s inputs using an input mask. This can limit

the types of characters they are allowed to input,

or can force a specific length. You’ll find this also

useful if you’re using the input tag to input a

password – which if you choose the passport

type, will be concealed rather than displayed. It’s

also possible to group the various types of input

element, enabling you to create complex

applications that behave more like HTML forms.

<wml>

<p>

Hello from the PC Plus Web

Workshop.

</p>

</card>

</wml>

Using the following snippet of code, you can

use a phone’s keys to move from one card in a

deck to another. A label displayed on the phone

menu as ‘Next’ will enable a user to move from

one card to another in a deck.

</do>

One thing to notice about WML is that the

<go> statement in this block has to be explicitly

terminated by a trailing slash – otherwise it will

cause an error, and won’t be displayed. You also

have to make sure that you only use lower case

for your WML tags, otherwise they won’t be

recognised by XML parsers. It’s also good form to

only use lower-case for your HTML tags, as the

next release of HTML will be XHTML 1.0, which

applies XML rules to HTML.

See the Code corner for a more complex piece

of WML code. It is a four-card deck that takes

user input and then displays it on the phone’s

screen. It might seem fairly simple by normal

HTML standards, but it gives you a good idea of

most of the main WML functions.

All the text blocks are surrounded by <p>...</p>

tags and the document has an XML document

type, so that it can be validated against the official

WML specification. You’ll need to include this

block at the start of every WML document you

create for it to be handled by most WAP gateways:

Get a toolkit

If you want to know more about WML,

download the Nokia WAP Toolkit from

www.nokia.com . Not only does it come with

plenty of documentation on WML in PDF

format, it also includes a set of simulators that

enable you to test your pages. These include the

popular 7110, as well as two of their latest

phones: the 6110 and 6150.

Nokia isn’t the only company with WAP

phones and simulators. Motorola has one, as

does Ericsson. Most of these companies will ask

you to sign up to their free developers

programmes, which are well worth using. They

provide support and plenty of information you

won’t find elsewhere – there were only two books

on WAP available at Amazon when this article

was written...

Of course, if you want to have something

more generic, you can use the tools provided by

the originators of the WAP standard: Phone.com .

You’ll also find that soon most of the commonly

available Web design tools will support WML.

Already HomeSite will handle WML documents,

and Macromedia are working with Nokia to add

support to Dreamweaver.

<?xml version=”1.0”?>

<!DOCTYPE wml PUBLIC “

//WAPFORUM//DTD WML 1.1//EN”

“http://www.wapforum.org/DTD/wml_1

1.xml”>

The DOCTYPE section includes the URL of the

official WML XML definition document.

Our example uses two cards to take inputs.

These use the two most common WML input

statements, the <select> block and an <input>

statement. The <select> block is just the same as a

standard HTML form select statement, and

behaves much the same way. You’ll need to give

it a title, as it’s usually displayed in its own screen

by most WAP browsers.

</p>

</card>

</wml>

Upload your pages

Once you’ve created (and tested) your first WML

pages, upload them to your Web space – making

sure you use the WML extension for all your

pages. You’ll also need to check that your ISP has

configured its Web servers to use the correct

MIME-type for WML decks (text/vnd.wap.wml),

so they’re handled correctly by the WAP gateways.

Then all you need is a WAP phone to see if you

can access your Web pages on the move... PCP

Simon Bisson

simon.bisson@pcpmag.co.uk

NEXT MONTH

<select name=”word” value=”Hello”

title=”Word”>

<option value=”Hello”> Hello

</option>

How to create more complex WML decks, using

WAP’s built-in scripting language WMLScript.

August 2000

PC Plus

165

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