Set Text in RadDropDownTree

[Vijay]

Hi All,

My question for client side code only using JavaScript.
I have a RadDropDownTree in my Form. In that DropDown I have some some data.
Suppose.
Central
    Middle Central
            Chicago
    Texoma
..
.
.
above mention is same data.

Now What I want is when User Select Chicago then Select text in client area of that dropdown should be anything like 'ABCD' or anything. I just want to set the
Selected text of that DropDownTree. I tried below mention code but is not working, In my RadDropDownTree, it still showing emptymessage.

var combo = $find("<%= RadDropDownLocations.ClientID %>");
combo._selectedText = "Davolio" + ";" + "Leverling";

Can someone guide me how can I set the text in DropDownTree

[Vijay]

Please someone help. Let me know in case of any more information