how to interface jquery ui components to backend

i don't have a lot of RIA experience, so please excuse my ignorance.

Currently, I'm looking at jQuery UI components to build an RIA. For example, there is a listbox style componenet. Do I have to provide the custom js code to make an XHR connection, code the backend to return an json object, then populate the jQuery UI component as des开发者_运维百科ired?

I guess what I'm trying to find out is, where does the responsibility end for jQuery UI components? Do the components themselves offer any methods for connecting to the backend?

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In contrast to, say, ExtJS, jQuery and jQuery UI don't deal with data loading at all. It's entirely up to you how data gets loaded.

That said, they do provide conveniences for doing so: the ajax function and its friends are much nicer to work with than XHR (and deal with JSON quite painlessly); the data facility is great for annotating your UI elements with the data they control or represent; and the templates plugin makes it easy to render your controls once you have the data.