Image disappears after click event

Hi,

I am working on nested gridview concept...

Here is the html source and the javascript function ... The image in the gridview disappears after a user clicks on it.. Why is it happening so? Please correct me.


===========================================
   AutoGenerateColumns="false" DataSourceID="SqlDataSource1" DataKeyNames="ItemID"
  ShowFooter="true" Font-Size="8.25pt"
  Font-Names="Tahoma" runat="server"
  Width="800px" onrowdatabound="GridView1_RowDataBound"
  BorderColor="#666699" BorderStyle="Solid">
 
 
 
 
 
 
  ', 'one');">
  " alt="Click to show/hide item location <%# Eval("ItemID") %>"  width="9px" style="border:0"  src="images/plus.gif"/>
 
 
 
 
 
 
 
 
 
   
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  <%--
 
       
        --%>
       
       
 
  Delete
 
 
  Add
 
 
       
       
       
       
 
 

" style="display:none;position:relative;left:15px;OVERFLOW: auto;WIDTH:97%" >
    AutoGenerateColumns="false" Font-Names="Verdana" runat="server" DataKeyNames="ItemID" ShowFooter="true"
 
 
  BorderStyle="Double" BorderColor="#0083C1">
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  <%--
 
 
  --%>
 
       
       
 
  Delete
 
 
  Add