Flexでpreloaderを設定する方法を検索していたら見つけたpreloaderのsample。
Ted On Flex: Flex 2 Custom Preloaders
Features:
– Preloader is available after application initializes.
– Preloader is faded in and out.
– Preloader supports GIF,JPG,PNG,SWF (Yes, Flash Preloaders are supported!)