I just tried out the HTMLIsland/HTMLContainer Developer Guideline and did the exercise.
But you cannot point to a html file (mime or url)? You can only define some little HTML parts with <div> tags and some values ( as in the exercise ).
I was thinking about Maps, Charts and other stuff that could've been integrated in webdynpro applications.
Does anyone know if it is possible, or an alternative without abandoning Webdynpro ABAP?