Prior to begin working in Flex 4, you must have some prerequisite knowledge of basic programming including concepts, processes, functions, constructions of programming, and softwares like XML, HTML and CSS.
The adequate knowledge of programming skills, and software will help you in assessing the fundamentals of Flex 4.
Flex 4 is the updated version of Flex 3 in which some extra features have been included, which ease the difficulty in developing some more lucrative and intuitive applications very easily.
For working in Flex 4, you will have to install the Flex 4 Software Development Kit (SDK) first. There are two ways of using Flex framework ? first one and most recommended way is to install FlashBuilder 4 Integrated Development Environment (IDE) which includes Flex SDK4 and other essential components like visual debugger, a visual profiler, a network monitor, and a Services view with service introspection, and Adobe Flash Platform. The second option is to install SDK 4 and configure it according to your settings. The SDK 4 too has similar components to FlashBuilder4 but lack of Graphic User Interface. It means SDK4 users will have to use the command prompt to compile, run, testing and debugging the applications.
The Flex 4 runs on two platforms ? Adobe Flash Player and Adobe AIR. The Flash Player runs on client?s browser while Adobe AIR on desktop. User can choose one of them accordingly.
To access back-end databases and other systems Flex has numerous networking APIs supporting everything from plain XML, JSON, SOAP Web Services, and optimized protocols like AMF. The Flex source code (.mxml and .as files) is compiled into.swf file that is executed at the client side by the ActionScript Virtual Machine in Flash Player or Adobe AIR.
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