Flex中动态加载图标。在Flex界面中，图标通常是预先指定的，而实际应用中，我们往往要根据需要动态加载图标。动态图标加载类可以解决这类问题-Flex in the dynamic loading icon. In the Flex interface, the icon is usually pre-specified, but the actual applications, we often have to dynamically load the needed icons. Dynami