xlink:actuate Actuating the Link

The intended behavior for a link when activated by an application, specifically, the timing for obtaining or retrieving the content of a link (for example, by a user clicking on the link to request the material, or by the material being automatically loaded with a document when the document or document component is loaded).
OPTIONAL on many elements; click for list and usage
Value Meaning
none The behavior is unconstrained, and no other markup is generally available in the link to assist an application in deducing the retrieval mechanism.
onLoad An application should retrieve the link at the same time a user obtains the initial document.
onRequest An application should only retrieve the link after a user has physically triggered the retrieval, for example, clicked on the link.
other The behavior is unconstrained, but other markup is generally available in the link to assist an application in deducing the retrieval mechanism.
Restriction @xlink:actuate is an optional attribute; there is no default.
Tagged Sample

Requesting an external link be retrieved, e.g., by clicking on it

...
<ext-link ext-link-type="url" xlink:type="simple"  
  xlink:role="http://www.mulberrytech.com/walkthewalk.html" 
  xlink:title="XML-based slideshow application"
  xlink:actuate="onRequest" xlink:show="new" 
  xlink:href="http://www.mulberrytech.com/slideshow/index.html">
 Mulberry Slideshow XML</ext-link>
...