unintended notification recursion

headers Zaven Arzoumanian | 3 Jul 15:45

Hi folks,

It seems I've coded myself into a corner.

See the attached partial screenshot of a panel from my Chaco-based
application. The various controls determine how a 2D dataset is binned
into a colormapped image. The point is to allow the user to choose the
number of bins, image boundaries, etc. The problem is that the user's
input for one trait has to change some of the other traits, which
triggers the notification handler in an endless loop.

I'm using extended traits names to register the handlers. This works
fine for the group labeled Filtering, but none of those traits depend
on each other. In the X and Y Imaging groups, changing the binning
boundaries for a fixed number of bins, for example, changes the bin
size. Each time the handler tries to adjust one of these traits
attributes, it gets called again, and I end up in an endless loop.

In hindsight, this should have been an obvious problem. What's less
obvious to me is how I can get around it. I've tried "unhooking" the
handler with the remove=True keyword in on_trait_change within the
handler, but that didn't work.

Any advice would be very welcome! If none of this makes any sense, I
can send a code snippet, but I'm pressed for time just before a trip
and was hoping someone had a quick solution.

Thanks!

Zaven

p.s. Thanks, Fred and Robert, for your responses to my earlier question
about reflecting plot limits in my view...