This question has been bugging me for a long time now. We have implemented "file open" type dialogs for filter plug-ins on the PC and later using Cocoa for modern PS on the Mac but with Carbon we never managed to get that to work (neither using CodeWarrior nor XCode). Eventually we implemented a work around I have never been happy with.
So if anyone could provide a code snippet for the PS CS4 SDK's Dissolve example that makes the Cancel Button open a file open dialog to read in a text file I'd be very grateful for that.
Pointing me in the right direction would also be welcome but we did try various things. I'm fear it will be a trivial matter but we'll see.