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Hi @Sean,
I’m concerned about this: why does pressing the button to set “node_index” also update the “node” and “coordinate” tables, even though they belong to “node_prop_group” and “node_index” is unrelated?
@Phu_Nguyen - the node_index property is used to keep track of which item within the collection (in this case the node_coll collection) is active or selected. Since we use node_index to indicate the active item in the list, when we update the index property, the active item in the list also updates.