I need to develop some HTML interfaces that will be highly dynamic. Here are a couple of examples of what I need to do.
Imagine 3 select menus: one listing Locations, another listing Systems (deployed at a location), and a third listing Components (that make up a system).
The interface would work such that by choosing a location, that location's systems would be displayed, and by choosing a system it's component's would be displayed. I have done this type of interface before with small data sets by dynamically creating Javascript that preloads arrays, but in the interface in question the Component's table will have thousands of rows so using the javascript technique would result in a very large script download.
Also imagine a form where if a user enters a valid model or serial number other fields such as part name, vendor, stored/deployed location would automatically be filled in. In other words, an HTML form that behaves more like a standalone or 4D client form.
I see possible solutions to either of these scenarios involving response to a "form event" that would trigger a query back to the database that would return some information that would be parsed and used to populate a specific select menu or form input field. I would also like to do this without having to request and render an entire page. I seem to recall discussions on this or other lists that hinted this could be achieved using Javascript and a small frame (invisible?) that is used as a "broker" to send and receive query results?
Is what I describe possible and if so, can anyone provide links or examples where I might learn more about this technique?
Thanks,
Brad Perkins Los Alamos National Laboratory
