The XML Web DataWindow builds upon the existing HTML Web DataWindow. It is designed to separate the content, the layout, and the style of the DataWindow on the Web.
The XML Web DataWindow uses an XML-based architecture and provides improved performance by using less bandwidth on round trips to the server. Markup that remains static for the life of the session needs to be downloaded only once.
The XML Web DataWindow uses the latest client-side XML technologies provided in the version 6 Internet Explorer and Netscape browsers, including XHTML, XML, and XSLT, and a standalone CSS style sheet with cascaded absolute positioning.
The XML Web DataWindow generator is invoked in the DataWindow engine from server-side code. It generates:
- An XHTML rendering of the DataWindow in a DOM tree.
- A CSS style sheet, using a DOM tree, that includes all the styling information of the DataWindow object's elements, including absolute positions in the cascade.
- A reverse transformation of the XHTML DOM tree into XML and XSLT DOM trees for Web publishing.
The XML tree contains the DataWindow data content for the page, and the XSLT tree contains the DataWindow object's structural layout.
- A small amount of script to perform explicit transformation on the client side.
The XML Web DataWindow client:
- Downloads the XML source file that contains the DataWindow data content for the page and the XSLT style sheet, which is cached locally.
- Performs a transformation using the XSLT processor.
- Outputs the XHTML result into a <div> section on the page.
- Downloads, caches, and applies the CSS style sheet for display in the browser.
Choosing a generation format You choose the generation format you want to use in the Web DataWindow DTC Properties dialog box or in a wizard such as the Web/JSP DataWindow Page wizard. The choices are XML for generating an XML Web DataWindow (separation of content, layout, and style with transformation to XHTML), XHTML for generating an XHTML Web DataWindow (XHTML is generated directly), and the existing HTML Web DataWindow.
Defining the structural layout of the DataWindow You can define the structural layout of the DataWindow and add your own customizations in an XHTML Template view that is similar to the XML view introduced in PowerBuilder 9.