Flex 3 FB4 Migration Tip

Question

Thanks to the help of several Adobe members I was able to successfully import a styled (.css) Flex 3 project into Flash Builder 4 and have it retain its aesthetic and functional attributes. I wanted to take a moment and share what I found with everyone, in case you may find yourself confronted with the same issues.
1.First, to bring in my Flex 3 project to Flash Builder 4 I needed to add a single line in my .css file:
@namespace "library://ns.adobe.com/flex/halo";
2. Next I had to add an Additional Compiler Argument. (Properties > Flex Compiler > Additional compiler arguments):
-theme=${flexlib}/themes/Halo/halo.swc
Basically there were a number of aesthetic breaks due to FB 4 (and newer SDKs) using the Spark component set. To ensure you Flex 3 application looks the same with the .css style, you'll need to specify that the application uses the Halo theme as the foundation.
I'm including a photo showing several aesthetic issues I had under Flash Builder 4 and the newer SDKs prior to this solution.
All of these have been fixed. Thanks again to all those at Adobe for the great support.
Jason Villmer
www.lucid.it
[email protected]

Answer 1

Glenn,
There is always the lure to immediately embrace the newest 
technologies. I'd been considerably eager to see what Flash Builder 
had to offer and it does, indeed, provide a broader landscape of 
possibilities. After everything has been said and done I believe the 
Flash Builder team should consider a Migration Assistant to help 
transition Flex 3 projects to the Flash Builder 4 code architecture. 
Upon importing a Flex 3 project the user could be asked if they would 
like to formally convert the entire codebase into a native FB 4 
project. It would then go through the document, possibly stopping 
occasionally asking for approval to do something, and update all 
relevant code so it becomes a true FB4 app. There could also be a list 
provided after this conversion that specifically outlines all changes 
made.
I've been working in Flex for a number of months now. Prior to this I 
was using the Flash IDE. Upon exploring Flex, the advantages were 
clear and substantial. Flex is absolutely outstanding for both 
designers and developers in my opinion. The issue, however, is that 
Flex users should be, above all, anxious to migrate to Flash Builder 
4, not worried. If a Flex 3 developer has finished a huge project 
(like you and I apparently) in Flex 3 we shouldn't have to go through 
all of our code trying to figure out what needs to be changed. There 
should be something that helps developers do that automatically.
Technology is relentlessly changing. Monthly, weekly, daily even. 
That's great but for something like Flex, new versions shouldn't have 
developers searching everywhere trying to find patchwork solutions.
The folks over at the Flash Builder 4 team have been great assisting 
both myself and the multitude of other users with their issues, so I'm 
pretty confident things will unfold well.
Jason Villmer
www.lucid.it
[email protected]