Restrict node drop action in some groups

GoJS
1

In my application, I have let’s say 100 nodes. Out of those 100, I have requirement that 50 nodes can be dropped in Group A ONLY, and the remaining 50 nodes can be dropped in Group B ONLY.

So I want to restrict the dropping of nodes in wrong groups. How can I achieve this?

I have implemented memberValidation function but it’s not helping me. Even though I return false from memberValidation function it still adds node to the group.

2

So you have checked that your memberValidation predicate is returning the correct true and false values?

Well, here is a sample that demonstrates what I think you are looking for, and also tests the effectiveness of member validation when dragging in from another Diagram as well as within a Diagram:
https://gojs.net/extras/addToGroup.html