You can try it yourself (being your sample), nothing changes. The problem arises when I drag from right tree and drop into left tree. DragDropMode='Move' removes the node from the right tree not from the left (Move – When a node is dropped, it is essentially removed from its original location and placed into the new destination target.).

Please let me know if and how this can be achieved.

Hi,

Any luck with the control?

Please let me know if you need of help further.

Best,

It seems not to be client-side as I was asking.

If I play with this long enough in my version locally when I "Move" a node from left to right, I can reproduce

Microsoft JScript runtime error: Unable to get value of the property '0': object is null or undefined ( shown at the bolded line below)

I believe it is when you move say item #5 and then move ANY item ABOVE where that was (like item #3).  It is like "the moved" elements are still being referenced by their index offset.

Is this a bug in set_value?  It should at least check for null before that array reference.

set_value:function(id, val, address)
{
var index = id[0];
var defaultVal = id[1];

if(typeof(val) == "boolean")
val = (val)?1:0;
var item = this._items[address][0][index]

if(item == null)
item = defaultVal;

if(!$util.compare(item, val))
this._transactionList.add_transaction(address, val, index);
else
this._transactionList.remove_transaction(address, index);
},