Flex components

As people are used to in different programming languages is putting everything in separate components or libraries. This is working fine for languages like Java since all libraries needed for your components are available for the server all the time. For Flex apps this is working different since everything needed for the flash file has to be compiled in the flash file, so if you create different swf files for your components it will add all elements you use in both of the swf files in both of them and that might cost you something on performance when using a slow connection.

If you look at all server communication parts of an application and look at the size of your swf as soon as you add one of these you might see it will grow a lot so if you want to use more swf files for one application and you use a lot of server communication make sure you add the communication part to one of your swf files and not to all of them. At this point Adobe is working on putting part of the flex tags inside the flash player and that will add that those parts will no longer be compiled in your swf file, so this might help a lot but it is not that far yet.