It seems to be an easy task but turned out a bit more complicated than expected: compiling a Flash Builder project out of the Flash IDE.

First of all you may ask why to do this – but sometimes workflow requires solutions like this one (especially when designers are involved…) .

My first thought on this problem was to use the entry point of the Flash Builder project as document class of the fla-file and point all source- and library-paths to the same folders. Well, the IDE tried to compile but threw some really weird and absurd compiler errors. I knew they were wrong because Flash Builder compiled the project just fine.

After I had double-checked all actionscript and compiler settings again I realized the difference between Flash Builder and the IDE: Flash Builder uses the Flex SDK to compile its AS3 projects while the Flash IDE points to following directory by default

$(AppConfig)/ActionScript 3.0/libs

That is definitely no pointer to any Flex SDK. So the next step was easy: looking up the path of the Flex SDK, point the Flash IDE to this path instead of the default libs directory and puplish the whole thing. This leads to a path like this:

C:Program Files (x86)AdobeAdobe Flash Builder 4sdks4.1.0

And – magic! – the movie compiles right out of the Flash IDE! Setting the right libs directory did the trick.