<subdialog>

Description

Invokes another dialog as a subdialog of the current one. The subdialog is a reusable dialog that allows values to be returned. The subdialog executes in a new execution context with all variables and execution state initialized. Values can be passed into the subdialog using <param> child elements; the subdialog must contain <var> variable declaration for each parameter. The original dialog can continue execution only when the subdialog executes the <return> element. Returned values are available as properties of the <subdialog> form item variable.

Note: The values passed in and out of a subdialog (using <param> and <return>) can be strings or any ECMAScript values (ex. numbers, pointers, objects, arrays, etc.).

Syntax


<subdialog
    name="string"
    expr="ECMAScript_Expression"
    cond="ECMAScript_Expression"
    src="URI"
    srcexpr="ECMAScript_Expression"
    namelist="variable1 variable2 ..."
    method="get" | "post"
    enctype="MIME_type"
    fetchaudio="URI"
    fetchaudiodelay="time_interval"
    fetchaudiominimum="time_interval"
    fetchhint="safe"
    fetchtimeout="time_interval"
    maxage="integer"
    maxstale="integer">
  child elements
</subdialog>

Attributes

Attribute	Description
name	The name of this subdialog. This variable can be referenced anywhere within the subdialog's form. The results returned from the subdialog can be retrieved as properties of the subdialog variable: `name.<returnVariable>`. Optional. (Defaults to an inaccessible internal variable.)
expr	An ECMAScript expression to be evaluated and used as the initial value of this subdialog. This subdialog will be visited only if the expression evaluates to `undefined`. Optional. (Defaults to undefined.)
cond	An ECMAScript expression to be evaluated and used as a boolean condition. This subdialog will be visited only if the expression evaluates to `true`. Optional. (Defaults to true.)
src	The URI of the subdialog. This can be the URI of another document, a dialog in the same document, or a dialog in another document. If this attribute is empty (""), the current document will be used. Exactly one of src or srcexpr must be specified.
srcexpr	An ECMAScript expression to be evaluated and used as the URI of the subdialog. This can be the URI of another document, a dialog in the same document, or a dialog in another document. If this attribute is empty ("") or set to the empty string ("''"), the current document will be used. Exactly one of src or srcexpr must be specified.
namelist	A space-separated list of variables to submit with the request. Optional. (Defaults to nothing.)
method	The request method: get or post. Optional. (Defaults to get.)
enctype	The MIME encoding of the submitted data. The following types are supported: application/x-www-form-urlencoded multipart/form-data Optional. (Defaults to application/x-www-form-urlencoded.)
fetchaudio	The URI of audio to play while waiting for the document to be fetched. Optional.
fetchaudiodelay	The length of time to wait at the start of the fetch delay before playing `fetchaudio`. Optional.
fetchaudiominimum	The minimum length of time to play `fetchaudio`, once started, even if the document arrives in the meantime. Optional.
fetchhint	Defines when the subdialog should be fetched. Optional. safe - only load the subdialog when needed
fetchtimeout	The length of time to wait for the subdialog to be fetched before throwing an `error.badfetch` event. Optional.
maxage	Indicates that this document is willing to use a cached copy of the subdialog only while the age of the cached copy is less than or equal to the number of seconds specified by this attribute. Optional.
maxstale	Indicates that this document is willing to use a cached copy of the subdialog that has exceeded its expiration time by as much as the number of seconds specified by this attribute. Optional.

Attribute Notes

An error event may be thrown if a reserved ECMAScript word is used as the name.
An error.semantic event is thrown if an undeclared variable name is used in the namelist.
An error.badfetch event is thrown if more or less than one of src and expr are specified.

Parents

<form>

Children

<audio>, <catch>, <error>, <filled>, <help>, <noinput>, <nomatch>, <param>, <prompt>, <property>, <value>, #PCDATA

Extensions

Added fetchaudiodelay attribute.
Added fetchaudiominimum attribute.

Limitations/Restrictions

When submitting ECMAScript objects in the namelist, the object will be "flattened", ie. all the object's properties will be submitted separately. For example, if object o has two properties, p1 and p2, such that o.p1 = "value1" and o.p2 = "value2", and the following subdialog is called:
<subdialog name="s1" src="test.jsp" namelist="o" ...>
then the HTTP request will contain o.p1=value1&o.p2=value2. Remember to retrieve the properties separately (as o.p1 and o.p2) in the server-side code used to generate the subdialog page.

The order in which the parameters are sent in an HTTP request may not be the same as the order specified in the namelist.

The use of POST is recommended when submitting a long list of variables. If you use GET (where the entire request is a single line), there may be a limit configured on the request length. Exceeding this limit will result in an error.badfetch. This limit may be configured by Squid on the Dialogic IP Media Server, or may be overridden by application server configuration.

Example

Document that calls the subdialog:


<?xml version="1.0"?>
<vxml version="2.0" xmlns="http://www.w3.org/2001/vxml">
  <form>
    <subdialog name="result" src="subdialog.vxml">
      <filled>
        Your account number is <value expr="result.acctnum"/>.
        Your phone number is <value expr="result.acctphone"/>.
      </filled>
    </subdialog>
  </form>
</vxml>

Document containing the subdialog:


<?xml version="1.0"?>
<vxml version="2.0" xmlns="http://www.w3.org/2001/vxml">
  <form>
    <field name="acctnum" type="digits">
      <prompt> What is your account number? </prompt>
    </field>
    <field name="acctphone" type="phone">
      <prompt> What is your home telephone number? </prompt>
      <filled>
        <return namelist="acctnum acctphone"/>
      </filled>
    </field>
  </form>
</vxml>