Treeview Control How can I trap a callback function

In my web application I have an Ajax Treeview control which populates its child nodes via AJAX, and all is working beautifully except that all our pages turn on a "spinny" image whenever there is a postback either full or partial my problem is how can I trap the completion of the ajax postback so I can turn the spinny off?

I cannot find a treeview event that I can trap on the client side to do this.

I expect someone has ran into this issue before so any help would be gratly appriciated.

I have only recently started using AJAX and so far everything I have seen has been really good but I would to solve this issue.

Cheers

John

How are you populating the tree? What "Ajax Treeview control" are you using?

You should be able to attach a callback handler that will let you get rid of the "spinny", but without knowing your approach I can't recommend how to do this in your instance.

-Damien

Hi Damien

Here is the markup for the treeview I have removed the styling for berevity

<asp:TreeViewID="tvwProcess"runat="server"EnableClientScript="true"OnTreeNodePopulate="GetChildren"PopulateNodesFromClient="true"Style="overflow: auto; height: 490px">

</asp:TreeView>

GetChildren is a serverside method which populates the expanded node

Does this give you enough info?

Thanks

John

You should be able to use the ClientScript.GetCallbackEventReference to get a reference to the callback and then hide the image using the callback method (seehttp://west-wind.com/weblog/posts/2302.aspx for an example).

Hope this helps...

-Damien

Hi Damien

re:

You should be able to use the ClientScript.GetCallbackEventReference to get a reference to the callback and then hide the image using the callback method (seehttp://west-wind.com/weblog/posts/2302.aspx for an example).

I tried your suggestion and got the example from west-wind working fine and also this example from Microsoft http://msdn2.microsoft.com/en-us/library/ms153106.aspx

the problem I still have with the treeview is what event to attach it to. The logical option would be the "OnTreeNodeExpanded" but that looks for a server side methodAm I missing something?CheersJohn

Hi,

At the client side,the"OnTreeNodeExpanded" is the click event of the parent Node.