Excerpt: Early Adopter VoiceXML: VoiceXML with XSLT (HTML and WML), Part 2

Next come the form level help dialogs, which here attempt to mimic typical responses likely from a real life call center, contrary to the advice of Chapter 6:

<help count="1">   
What seems to be the trouble?   
<reprompt/> 
</help> 
<help count="2">   
Come on - isn't this easy enough to understand?   
<reprompt/> 
</help> 
<help count="3">   
Hey <xsl:value-of select="customer/firstname"/>, 
are you stupid or something?   
<reprompt/> 
</help>

The design specifies that the main menu command is always available. We can implement that with a global VoiceXML <link> element:

<link next="#mainMenu">   
<grammar type="application/x-jsgf"> 
main menu 
</grammar> 
</link>

Again, we use the information from the XML file to customize the prompts for the user. This form welcomeMessage corresponds to the "welcome message" box in the interface design diagram earlier.

<form id="welcomeMessage">   
<block>     
<prompt bargein="false" timeout="0.1s">       
Hello, <xsl:value-of select="customer/firstname"/>.       
Welcome to the my rubber bands 
dot com voice order status system.     
</prompt>     
<goto next="#mainMenu"/>   
</block> 
</form>

Next, we come to the mainMenu form, the primary form of the voice application. There is a form level <nomatch> element here to transfer control flow to the errorHandler form when an utterance doesn't match the grammar. This form is used for most no-match events throughout the application, to keep track of the total number of such errors that have occurred this session. The <noinput> handler here ensures the main menu is repeated when the user doesn't respond to the prompt. In a future version of the product, the designers may implement some kind of timeout to restrict the number of loops, and disconnect the user if there is no response for a long time, but this issue need not concern us now.

<form id="mainMenu">   
<nomatch>     
<goto next="#errorHandler"/>   
</nomatch>   
<noinput>     
<goto next="#mainMenu"/>

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This article was originally published on February 14, 2002