Why the same UI window (Data-shapes) opens twice when running the routine. How can I solution this problem?
Would be helpful to see the graph, but it should only fire once unless there is more than one instance of the node.
This can sometimes happen when updates are made to the graph and nodes execute out of order. Try running via player and/or re-open the graph.
Give Dynamo Player a try as Jacob has indicated and if it does the same, maybe worth if a “Wait” style node is implemented to help with this.
You can also use the Toggle connector on the MultipleInputForm++ node. Connect a boolean node there, run with toggle->false so no UI window will appear. Change the toggle->true => window appears only once.
The problem didn’t happen again.
(I added a “Wait” style node.)