This is a technical diary, short entries tracking the migration of the Vaccine Ingredients Calculator from Flex 3 to Flex 4: a non-trivial effort that I’m approaching with both excitement and trepidation.
I’ve been meaning to start this project for the past 6 months, but there has been too many enhancements that I’ve wanted to roll into the VIC. Then, a few days ago, I found a good article on migrating flex apps and, after deploying a new version of the VIC today, figured that the time was right to begin.
The VIC is hosted on Google Code and stored in svn. So the first thing I did was to create a new branch called flex4 from within subclipse. Next, I changed the VIC’s Flex SDK version to 4.1 (in Flex compiler properties). The change generated 28 errors and 14 warnings. The errors were all related to style attributes:
Initially, this made my stomach turn; I didn’t understand what it meant. Its a result of a big change made in the Spark component architecture pertaining to how styling and skinning is done (see video tutorial “Introducing Flex components and controls” on this page for a good overview.) Fortunately, these errors can be fixed with no coding changes by choosing the Halo theme:
All compile errors are gone, but I’m left with 66 warnings to work through. I did a quick check: the VIC runs but there are some problems; however, all 459 of our FlexUnit tests run successfully. This is enough for today.
