Question on enhancing regrouping tree view

Hello Team,
can you please help how we can add the lines mentioned in below screenshot(highlighted in red) on dropping elements in a group?
As the current regrouping tree view seems having lots of borders for many nested groups.

in myDiagram.groupTemplateMap.add(“OfNodes”,{…}
this.goMake(go.Shape, “Rectangle”, { fill: null, stroke: “white”, strokeWidth: 0 }),
this helped me removing borders, any example stating how i can add the lines stated in below screenshot(highlighted in red) on dropping elements ?

Did you mean to link this sample? If you want to add lines to the Tree View on the left side, you could modify the link template to something similar to what’s commented out in the TreeView sample code:

myTreeView.linkTemplate =
  $(go.Link,
    { 
      selectable: false,
      routing: go.Link.Orthogonal,
      fromEndSegmentLength: 4,
      toEndSegmentLength: 4,
      fromSpot: new go.Spot(0.001, 1, 7, 0),
      toSpot: go.Spot.Left
    },
    $(go.Shape,
      { stroke: 'gray' }
    )
  );

thank you!
Does this mean replacing below code
// without lines
myTreeView.linkTemplate = $(go.Link); code with your code will make that structure on left hand side?

Yes, that’s the code you’ll want to replace.

Thanks for quick help…I need treeview as a main diagram ,how can I allow the drop from a pallete and make the items from pallets in some dropped group parents as their children.
i can do allowDrop: true, mouseDrop: in tree view.
but it is not dropped in respective focused parent.
when i try to implement like the regrouping demo i get error.
Trying to set undefined property “mouseDragEnter” on object: Diagram “myTreeView”

I’m not totally clear on what you’re looking to do.

So you want to have some palette of various nodes that can be dragged to a Tree View and added as a child of whichever Node they were dropped on? You may not need Groups at all, you might just want to use a TreeLayout similar to the one in the Tree View sample.

Yes correct…
More information on this:-
In this sample Regrouping Demo
i need the Tree View as a main myDiagram and palette of various nodes that can be dragged to this myDiagram.
Issue i am facing:-
unable to make a Tree View of dropped element of whichever Node from palette on myDiagram.(like how myDiagram behaves on regrouping.html)

Here’s a codepen that demonstrates drag and drop into a Tree View: https://codepen.io/jhardy/pen/xrGddm