How to hide the animate nodes under the parent node when click expand button to collapsed?

GoJS
1

Hi, I have a problem when click expand button. The animate nodes will cover above the parent node. Can I put them under the nodes when doing the animation?
Snip20220413_11

2

I think you have them be in a Layer that is behind the Layer that the expanded Node is in.
I have not tried this, but you could experiment by declaring an “AnimationStarting” DiagramEvent that puts the expanded Node in the “Foreground” Layer. In an “AnimationFinished” listener you could put it back to its default Layer.