> I've got some scenarios where binding does not fire if I use ac.addItem or > ac.removeItem. > But it will fire if i use ac = new ArrayCollection......
Sounds like you're binding to just the ArrayCollection instance variable and not taking the second step and listening for the collection events. This should only happen in a custom component because all of the Flex 2 dataProvider-based components handle this correctly. In a custom component/class, if you just bind "myAC" the binding only fires when the instance in the "myAC" variable changes (when you do "new ArrayCollection()..."). The right thing to do (if you want dataProvider-like functionality) is to add a collection event listener to your dataProvider in its setter and then handle those events. If this is happening in apps that are only vanilla Flex components (nothing custom), then there must be something wrong with the wiring in your app somewhere... Troy.
