preloading a dynamic classes which loads its own content

How d开发者_StackOverflow社区o you preload dynamic classes which loads its own content? cause theoretically speaking the classes doesn't have a size yet until it loads its content right?

you would have to initialise the object, start it loading and then get the size of the file(s) from it to do a preload animation. therefore you cannot preload an uninitialised class as you dont know the size of it untill it is loading.