Node not resizing after group is resized

hi, i have a problem, before adding the functionality of the group resize my node is getting resized properly, but when i have added the functionality for group to resize, then my node is not getting resized, its throwing the error of cannot read i of undefined.

“resizingTool.computeMinSize”: function() {
var group = this.adornedObject.part;
var shape = group.resizeObject;
var membnds = group.diagram.computePartsBounds(group.memberParts);
membnds.addMargin(GroupMargin);
membnds.unionPoint(group.location);
return membnds.size;
}

the above is the code which i have added in the go.diagram.

what should i do for making the node to resize?

If you step through that code, where is the error?

Might it be that the ResizingTool.adornedObject.part is not a Group but a regular Node? In that case you can either return a suitable value or return the result of calling the base method, go.ResizingTool.prototype.computeMinSize.call(this).

ya, actually, what i am saying is that, in normal condition, the node is working properly, i.e., the node is getting resized properly to its minSize. but when i add the resizingTool.computeMinSize to the go.Diagram, the sizing functionality is missing, and i am getting the error of “i” is undefined.

i have took the code from this link Simple Group Resizing

It’s hard to help you if you do not answer my questions or follow my suggestions for what I am guessing your problem is.