We use Tibco General Interface for our RIA presentation layer. The server side is .NET application which exposes data as Web service etc.,
Up till now we have been able to develop the presentation part without using any ASP.NET controls - using all the standard components provided by Tibco GI library.
Currently some parts of the application require us to use DevExpress controls for UI interactions - like the grid control etc.,
The best (easiest i.e) way we felt this can be incorporated into the existing framework is by having IFrames. The only issue is the user could open 25 to 30 dialogs within the same page and that would be as many IFrames.
Is this okay from performance point of view? In Tibco GI the entire application is loaded into a <div> element. This would mean a single <div> hosting alteast 30 IFrames. Also, would removing the IFrame from the DOM free up memory?
I am not sure if there is any alternative (apart from rewriting the framework and making it all server side controls).
It depends a lot on what browser you're using. If you're having to deal with IE6, consider that panicking may be a reasonable option. Working with its DOM—including iframes—leaks memory like a sieve with Free Extra Bonus Holes. At least if you—ahem—close the "tab", absolutely all the memory it used is freed, which is better than any modern browser.
If you're targeting decent browsers, don't worry too much about it. The best way of finding out, though, is almost always to try it. Then you get real data.
Try it (simulate it, perhaps, by writing two simple pages, one with the control, one with 30 iframes containing copies of the other) and see what the results are.