Text area

Basic usage
<xf:textarea ref="text"/>
Unformatted text
By default, the text area control is rendered as a regular multi-line text area:
Multi-line text area in Orbeon Forms
Attributes
With the standard appearance, the following attributes are available:
xxf:cols: same as HTML input cols attribute (prefer using CSS for this)
xxf:rows: same as HTML input rows attribute (prefer using CSS for this)
xxf:maxlength: same as HTML 5 input maxlength attribute (not all browsers support this attribute, and some have bugs)
You can add the appearance="xxf:autosize" attribute on the <xf:textarea> to get the textarea height to automatically adjust to its content.
Placeholder for label and hint
[SINCE Orbeon Forms 2017.1]
Per-control properties
The label or hint associated with <xf:textarea> may have the minimal appearance:
<xf:textarea ref=".">
    <xf:label appearance="minimal">Comment</xf:label>
    <xf:hint>Hint</xf:hint>
</xf:textarea>
​
<xf:textarea ref=".">
    <xf:label>Comment</xf:label>
    <xf:hint appearance="minimal">Hint</xf:hint>
</xf:textarea>
This causes either the label or the hint to appear on the background of the field when it is empty. If both the label and hint have a minimal appearance, the label wins.
Orbeon Forms leverages the HTML 5 placeholder attribute for browsers that support it (Firefox 3.5+, Chrome, Safari, Opera), and simulates the HTML 5 placeholder functionality in JavaScript for browsers that don't support it (IE8 and IE9). In that case, you can customize how the placeholder is displayed by overriding the CSS class xforms-placeholder.
Per-form properties
NOTE: This works the same as the per-form properties for <xf:input>.
The XForms oxf.xforms.label.appearance or oxf.xforms.hint.appearance (or the corresponding xxf:label.appearance and xxf:hint.appearance attributes on the first <xf:model> element) allow setting a default for the labels and hint appearances for the entire form.
The default values is full:
<property
    as="xs:string"  
    name="oxf.xforms.label.appearance"                            
    value="full"/>
​
<property
    as="xs:string"  
    name="oxf.xforms.hint.appearance"                             
    value="full"/>
Supported values for oxf.xforms.label.appearance:
full: labels show inline above the control (the default)
full minimal: labels show as an HTML placeholder within the field when the field is empty
Supported values for oxf.xforms.hint.appearance:
full: hints show inline below the control (the default)
full minimal: hints show as an HTML placeholder within the field when the field is empty
tooltip: hints show as tooltips upon mouseover
tooltip minimal: hints show as an HTML placeholder within the field when the field is empty
When the global property includes minimal, it is possible to override the appearance on the control with appearance="full":
<xf:textarea ref=".">
    <xf:label appearance="full">Comment</xf:label>
    <xf:hint>Hint</xf:hint>
</xf:textarea>
​
<xf:textarea ref=".">
    <xf:label>Comment</xf:label>
    <xf:hint appearance="full">Hint</xf:hint>
</xf:textarea>
Formatted text
Enabling the rich text editor
If you add the attribute mediatype="text/html" on your <xf:textarea>, then the text area will be rendered as an HTML editor:
Rich text editor in Orbeon Forms
HTML cleanup
When using the attribute mediatype="text/html", the HTML area will clean-up the HTML typed or pasted in the editor. This is done for two reasons:
Avoiding a "tag soup" – The HTML received from the browser can be grossly invalid, and contain foreign elements, in particular when pasting text copied from another application (e.g. Microsoft Word) into the editor. If kept as-is, the "HTML" you capture this way is then harder to process.
Security – If you don't clean up the HTML, and if your application sometimes shows HTML entered by one user to another user, your application can pose a security threat. A malicious user M can insert in the HTML some JavaScript that exploits a security bug in a given browser. When a victim V loads a page that displays the HTML added by M, that HTML (with the script it contains) runs and can potentially compromise V's computer.
The cleanup is performed in two stages:
1.The HTML goes through TagSoup and converted into a well-formed XML fragment.
2.The XML fragment goes through an XSLT transformation, which removes all the <script> and their content, and only keeps well-known elements in the HTML (such as <b>, <p>, <a>...). This is done in clean-html.xsl, which is bundled in orbeon-core.jar (prior to Orbeon Forms 2016.3, in orbeon-resources-private.jar). Should you want to change the way HTML is cleaned, you can override this file by placing your copy under the same path in your resources (typically WEB-INF/resources/ops/xforms/clean-html.xsl).
Limitations
HTML Editor in incremental mode – When the HTML editor is in incremental mode, XForms code can't change the value shown by the editor as long as the editor has the focus.
Output
Button