ABSTRACT

XML-based language. XML elements can have the same name but different sources. To overcome this situation the notion of namespace has been introduced. A namespace is a set of names identified by a unique URI (uniform resource identifier), which represents the source of the names. For example, the Flex 4 SDK includes two different component libraries, the old Flex 3 and the new one. Since some of the components have the same tag name (e.g., Button ), for the Flex compiler it is impossible to detect which is the button to use. By using a different namespace you can easily specify which component to use: mx for the old library and s for the new one.