DESIGN THE ACTIVE DESKTOP ITEM WEB PAGE
The HTML page you use for your desktop item must be small. I don't mean bytewise, but physical size. My desktop item measures 210 pixels wide and 100 pixels tall. Users don't want desktop items that take up the whole screen. They just want it to sit in the corner. From what I've read, you should make your desktop item take up no more than one-sixth the area of the screen, equivalent to about 200x200 pixels. Your desktop item only has to have a couple lines. Mine is for my HTML4 e-letter. It is updated every week (it's a weekly e-letter). My desktop item has a link to the online issue and gives a 2-3 line outline of the current issue. When you make the Web page, be sure to include technologies such as DHTML, CSS and HTML4. You know the user will be using IE4, so take advantage of what that browser has to offer.
CREATE THE CDF FILE
Once you have the HTML page, you need to create a
Channel Definition Format (CDF) file that takes care of the whole download and update
thing. CDF files are written in XML (the brother of HTML). Here is an example CDF file:
You would save that in text format with the suffix .cdf. After the opening XML and channel tags, we have the schedule tag. The IntervalTime is how often you want the desktop item to be updated. Set this to as often as you update the HTML page you created earlier. EarliestTime and LatestTime are the earliest and latest times you want the desktop item to be updated. If your desktop item is popular, you are going to want the two times to be fairly separated. If everyone were to update their desktop item at the same times, phone lines would get clogged and the download would be very slow.
The Item tag is the HTML page that will serve as desktop
item. Next you have the title of the desktop item. This is needed so that when a user goes
to manage his desktop items (right-click desktop, Active Desktop, Customize my
Desktop...), there will be a title for the desktop item you created. The usage tag is
where you set up the size and other things for your desktop item. The first item is
required. It is the page that shows up on the desktop. You can
FTP the CDF file and the HTML pages that you created to
your Web server to that Web surfers may download the desktop item to their computers.
Now you want to offer the desktop item to your users. You
need to create a link to the CDF file. Do this just as you would make an regular link,
except trade the CDF file for the HTML page in regular links. You can also get that cool
"Add to Active Desktop" button. This button is available from the Microsoft site
This tutorial is written and contributed by Matthew Clemente, professional web designer and owner of FlamingoLingo.com Visit FlamingoLingo for tutorials and tips on HTML 4, CSS, DHTML, and more. There is also a weekly newsletter you can subscribe to to get all this info delivered to your email!