Reducer / AnimatingTabView --> AnimatingScrollView

FROM : I. Savant
DATE : Thu Aug 10 17:09:54 2006

List:

  Here's one I'm hoping some Core-Image-proficient developers can 
help me with. I'm trying to apply the Reducer example's 
AnimatingTabView concepts to NSScrollView. Specifically, I want the 
transition to occur when the document view is set/changed. Though the 
transition is delayed (indicating the blocking animation is taking 
place), the problem is that the scroll view's contents switch to all 
white for the duration of the animation, then to the new document 
view. No pretty CI stuff is happening.

  I've subclassed NSScrollView and copy-and-pasted everything 
directly from the example. I changed the -selectTabViewItem: method 
to -setDocumentView: and modified the contents of this method to 
match (ie, using the scroll view's -setDocumentView: rather than the 
tab view's -selectTabViewItem:). I also eliminated the step of 
determining the transition filter to use since I'm only interested in 
the CIDissolveTransition filter. The resulting code to construct the 
filter (which is now directly in the -setDocumentView: method) is:

  transitionFilter = [[CIFilter 
filterWithName:@"CIDissolveTransition"] retain];
  [transitionFilter setDefaults];
  [transitionFilter setValue:initialCIImage forKey:@"inputImage"];
  [transitionFilter setValue:finalCIImage forKey:@"inputTargetImage"];

  All the rest works the same. I'm wondering whether or not there's 
something inherently different about a scroll view / clip view / 
document view set-up than a tab view that negates this approach. If 
so, how can I get around it. If not, what the heck am I doing wrong?

  Thanks in advance!

--
I.S.