All the generic extensions are in the namespace
http://orbeon.org/oxf/xml/xbl, and the usual mapping of this namespace is
xxbl:container attribute on
xbl:binding allows specifying the name of the HTML element that the XBL binding uses to encapsulate content. By default, this is
xh:div. Here is how to change it to
<xbl:binding id="my-binding" element="fr|my-binding" xxbl:container="span">
xbl:attr attribute does not support accessing attributes other than those positioned exactly on the bound element. This is a serious limitation. The Orbeon Forms implementation adds an extension attribute,
xxbl:attr, which takes an XPath expression:
xxbl:attr="xf:alert/(@context | @ref | @bind | @model)"
When more flexibility is needed than XBL can provide, the
xxbl:transform attribute is your friend.
<xbl:template xxbl:transform="processorName">Transformation (inline)</xbl:template>
Orbeon Forms runs the processor specified by this attribute connecting its
config input to the content of the
xbl:template and its
data input to the bound element and replaces the content of the
xbl:template by the
data output of the processor. The most frequent expected use is to run XSLT transformations. For instance, to create a widget that alternates styles in table rows within an
<xbl:binding id="foo-table-alternate" element="foo|table-alternate"><xbl:template xxbl:transform="oxf:xslt"><xsl:transform version="2.0"><xsl:template match="@*|node()"><xsl:copy><xsl:apply-templates select="@*[not(name() = ('style1', 'style2'))]|node()"/></xsl:copy></xsl:template><xsl:template match="foo:table-alternate"><xh:table><xsl:apply-templates select="@*|node()"/></xh:table></xsl:template><xsl:template match="xf:repeat/xh:tr" ><xf:var name="position" value="position()"/><xf:group ref=".[$position mod 2 = 1]"><xh:tr xbl:attr="style=style1"><xsl:apply-templates select="@*|node()"/></xh:tr></xf:group><xf:group ref=".[not($position mod 2 = 1)]"><xh:tr xbl:attr="style=style2"><xsl:apply-templates select="@*|node()"/></xh:tr></xf:group></xsl:template></xsl:transform></xbl:template></xbl:binding>
This component can be invoked through:
<foo:table-alternate class="gridtable" style1="background: red" style2="background: white"><xh:tr><xh:th>Label</xh:th><xh:th>Value</xh:th></xh:tr><xf:repeat ref="item"><xh:tr><xh:td><xf:output value="@label"/></xh:td><xh:td><xf:output value="@value"/></xh:td></xh:tr></xf:repeat></foo:table-alternate>
xbl:template/@xxbl:transform="oxf:xslt" attribute specifies that its child element (
xsl:transform) is considered as an XSLT transformation, runs against the bound element (
foo:table-alternate), and the result of this transformation is used as the actual content of the
The result of your transformation will often contain XBL attributes, and in this sample
xbl:attr attributes are used to set the
style of the rows with:
The result of the transformation has to be a (well formed) single rooted XML fragment. This might seem obvious, but that means that you might have to encapsulate the sub elements of
xbl:template in an XHTML
span compared to what you would have done if you were not applying a transformation.
The transformation has full access to the bound element and can transform any of its child nodes or attributes. To keep things as encapsulated as possible and not change the behavior of bound elements that are potentially embedded, it is a good practice to define tight transformation templates that affect only the nodes that are meant to be transformed. In the example given above, one might for instance argue that
<xsl:template match="foo:table-alternate/xf:repeat/xh:tr"> would be safer than
You can use
<xsl:message terminate="yes"> to report to the user errors that occur during the XSLT transformation. For example:
This results in an error will be output in the log, and an error message will show in the browser.
<xxbl:global> element allows an XBL binding to place global markup that is included in a page only once.
<xbl:xbl><xbl:binding element="fr|foo"><xxbl:global><!-- The single global dialog --><xxf:dialog id="my-dialog" level="modal" model="my-dialog-model"><xf:label>My Global Dialog</xf:label><!-- Dialog model --><xf:model id="my-dialog-model">...</xf:model>...</xxf:dialog></xxbl:global><xbl:template>...</xbl:template></xbl:binding></xbl:xbl>
How this works:
The global markup is included at the end of the top-level XForms document, as if you put it there by hand.
If the XBL binding is not used, the global markup is not included.
Ids on elements in global markup must be made unique by the component author, as those ids become global as well.
The component can dispatch events to global controls if the outer scope is the top-level scope, with the
xxbl:scope="outer" attribute. For instance, if in the
<xxbl:global> you defined an
<xxf:dialog id="my-dialog">, then from within the component, you can run the following action:
<xxf:show dialog="my-dialog" xxbl:scope="outer"/>
NOTE: A future enhancement to this feature might restrict id and XPath scope of global markup to that of the XBL binding.
This attribute, placed on a local XForms instance, tells the XBL engine to automatically mirror changes between that instance and the XBL component's bound node.
For mirroring to work, the XBL component must either:
if it has an XPath node binding: be bound to an element node
if it doesn't have an XPath node binding: be in the XPath context of an element node (done for compatibility with Form Builder section templates)
At most one instance in a given XBL component may have
when the XBL component becomes relevant
the XBL instance is first initialized as usual
then if the XBL binding or context points to an element, that element is extracted to become the root element of a new element, which replaces the XBL instance
when updates (value changes, inserts, deletes) take place on the XBL instance, these changes are mirrored outside
when updates (value changes, inserts, deletes) take place outside, these changes are mirrored on the XBL instance
<xbl:binding id="fr-gaga" element="fr|gaga" xxbl:mode="binding"><xbl:implementation><xf:model id="gaga-model"><xf:instance id="gaga-instance" xxbl:mirror="true"><empty/></xf:instance></xf:model></xbl:implementation></xbl:binding>
[SINCE Orbeon Forms 2018.1]
This attribute allows including a part of the resulting tree only if a particular attribute is present on the bound node.
<xf:group xxbl:use-if-attr="prefix" class="add-on" ref=".[xxf:non-blank($prefix)]"><xf:output value="$prefix"/></xf:group>
xf:group element will ony be included if the bound node contains an attribute named
prefix. Otherwise the entire subtree will be omitted.
This also checks properties such as
oxf.xforms.xbl.fr.currency.prefix and if the value of the property is found and not empty, it is as if the attribute was present on the bound node.