Computer Underground

Creating A WML Deck In this example, we’ll start by creating a WML deck that allows us to first select a username from a list, enter in a password, then have our selections repeated back to us. This will illustrate the basic handling of user input, events, and variables all within one deck using multiple cards. Listing 1 - WMLExample.wml

<wml> <do type="accept" label="Password">

UserName: <select name="name" title="Name:"> John Doe Paul Smith Joe Dean Bill Todd

<do type="accept" label="Results">

Password:

You entered:
Name: $(name)
Password: $(password)

As you can see, the prolog of this document contains the XML version number to be used as well as the Document Type Definition to be referenced. Following this comes the wml

document element (the deck) that contains three cards: Login, Password, and Results. Each of these cards is defined using the element. Because the Login and Password cards also define events, they use the element to define the event to be triggered. Figure 1 shows the initial card loaded in a test browser.

Figure 1 When the "accept" type of the do element is encountered, it is displayed as an option on the WAP device display (see Figures 2, 3, and 4).

Figure 2

Figure 3

Figure 4

Selecting this option causes the element to be analyzed. If you are familiar with the anchor tag () in HTML, you know that it specifies an href attribute that tells the browser where to link to if this anchor is selected. The WML element’s "href" attribute works in the same manner. As with HTML, to link to another card in the document, you simply prepend a # symbol before it. For example, to link to the Results card, we define the following element:



This Results card makes use of variables by retrieving and displaying the contents of the name and password variables. Recall that variables are substituted into a card or deck by using the following syntax:

$(variable_name)