Add icon next to leafnode of asp Tree view

Question

Here is my code like this:

"trwStates" runat="server" ExpandDepth="0" ImageSet="XPFileExplorer" MaxDataBindDepth="3" OnSelectedNodeChanged="trwStates_selectednodechanged">

"...leaf.png" HorizontalPadding="5px" NodeSpacing="1px" />
     "...parent.png"
      HorizontalPadding="5px" NodeSpacing="1px" />
"...root.png" HorizontalPadding="5px" NodeSpacing="1px" />

My final output on my page is:

 

[root.png] RootTest

            [parent.png] ParentText

                                 [leaf.png] leafText [I want to put Image here -only at leaf level]

 

I want to put an image at that point and fire a click event on that? I tried in google saw many pages but not helpful.

 

many thanks,

Darma