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Integrating Flex Apps with Browsers and AJAX

I got in a little late on this presentation, but it outlined some of the problems coupling these two technologies and some solutions to these problems.

Jason Williams presenting
The FlexAjaxbridge was the first solution shown - coupling Flash Charts with HTML navigation. I had seen this example some weeks ago on his blog, but the thing I missed out back then was the fact that this was a mix of HTML and Flash. The examples looked so good that I actually thought everything was done in Flash. Well done when one does not notice the blend! That's how it should be done. He also showed an image viewer blending HTML with a dynamic 3D-ish navigation.

One of the problems with this approach is that Objects marshaled across the bridge are not released from memory, so be aware of this if you use the FlexAjaxBridge. This is likely to be solved in the next version. Next up was a brilliant comparison of Data Loading Metrics. Christophe Coenrats actually showed me a bit about this yesterday and it clearly shows that if your application will display a lot of data, you should consider using Flex rather than AJAX because of performance.

His metrics example pulls 5000 rows of data from a server using various technologies. The time indicated here is the combined load time and parse and render time and the example clearly shows the speed benefit that using a binary Flash protocol offers over standards based and human readable Ajax : Ajax HTML (6 sec), Ajax XML(20 sec), Ajax JSON (18 sec), Flex E4X (5.5 sec), Flex AMF (1 sec), Flex Paged (0.1 sec). This last technique is using Flex Data Services (FDS) and pulls in only 200 rows at a time, but as soon as the user scrolls down the Datagrid, Flex will go out to get the correct page of data. There is a small flicker every time the data set is loaded, but this is barely noticeable. This way you only download what the user needs, thus saving both bandwidth and data loading time. The paging is automatic if you are using FDS.