Binding NSButton enabled state

FROM : Lorenzo Thurman
DATE : Sat Apr 19 20:08:07 2008

I have two NSTableViews, tableA and tableB, each managed by separate
NSArrayControllers. When a selection is made in either table, an instance
variable is set. I want to have an NSButton's enabled state to 'YES'
whenever the instance variable is set. I've tried binding the button to the
instance variable through my controller, but
the button becomes enabled only when there is selection in tableA, but it
does not enable when a selection s made in tableB. As a matter of fact, if
the button is enabled and I make a selection in tableB, the button will
disable. It will re-enable by clicking in tableA, but then disable again
when clicking in tableB. Does anyone have any pointers on how I can make
this work?

--
"My break-dancing days are over, but there's always the funky chicken"
--The Full Monty