From Wikibooks, open books for an open world
Jump to navigation Jump to search

Motivation[edit | edit source]

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.

Screen Image[edit | edit source]

A simple XForm button and the resulting message

Sample Program[edit | edit source]

      <title>Button Example</title>
         <xf:instance xmlns="">
          <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>

Discussion[edit | edit source]

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.

Styling a Trigger[edit | edit source]

By default each trigger looks like an HTML button. You can turn this off by setting appearance="minimal".

<xf:trigger appearance="minimal">

Having a Button Trigger Multiple Events[edit | edit source]

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:action ev:event="DOMActivate">
      <xf:send submission="getTime"/>
      <xf:send submission="getTemperature"/>

References[edit | edit source]

W3C trigger element

FireFox CSS styling hints

Next Page: Controlling Button Appearance | Previous Page: Upload
Home: XForms