XForms/Trigger
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[edit] Motivation
XForms creates a general way to represent a button that will work on web pages and cell phones. But it is not called "button" as in most other systems. It is an abstraction or generalization of a button called a trigger. A trigger is an abstraction of a web button or another event such as a button on a cell phone. Using a trigger abstraction allows your XForms to be more portable.
[edit] Screen Image
[edit] Sample Program
<html xmlns="http://www.w3.org/1999/xhtml" xmlns:xf="http://www.w3.org/2002/xforms" xmlns:ev="http://www.w3.org/2001/xml-events" > <head> <title>Button Example</title> <xf:model> <xf:instance xmlns=""> <data/> </xf:instance> </xf:model> </head> <body> <xf:trigger> <xf:label>Button</xf:label> <xf:hint>If you press this you will get a hello world message.</xf:hint> <xf:message level="modal" ev:event="DOMActivate">Hello World!</xf:message> </xf:trigger> </body> </html>
[edit] Discussion
This example has both a label and a hint. XForms also has help text that can be used but the way help is implemented is implementation specific.
[edit] Styling a Trigger
By default each trigger looks like an HTML button. You can turn this off by setting appearance="minimal".
<xf:trigger appearance="minimal"> <xf:label>Save</xf:label> </xf:trigger>
[edit] = Having a Button Trigger Multiple Events
When you press on a button (trigger) you sometimes want the trigger to do more than a single submission. Whenever you want to do this you can just add an action element and wrap multiple sends in the action:
<xf:trigger> <xf:label>Submit</xf:label> <xf:action ev:event="DOMActivate"> <xf:send submission="getTime"/> <xf:send submission="getTemperature"/> </xf:action> </xf:trigger>
