TreeView and UpdatePanel

Hi:

I am experimenting with TreeView in ASP.NET 2.0 and ATLAS.

I have placed a simple TreeView inside an UpdatePanel, and populated it from an XML file as follows:

   <asp:TreeView ID="tvSysMgtNavigation" ExpandDepth="0" runat="server"> <DataBindings> <asp:TreeNodeBinding DataMember="Item" TextField="Name" SelectAction="None" /> <asp:TreeNodeBinding DataMember="ItemLine" TextField="Name" /> </DataBindings> </asp:TreeView> <asp:XmlDataSource ID="XmlDataSource1" runat="server" DataFile="~/App_Include/Management.xml" />

So, when the TreeView Loads inside the UpdatePanel, only the root is show to be expanded. When I click on the "plus" near the root, I get this javascript exception:

Microsoft JScript runtime error: Object expected

and Visual Studio 2005 show the exception at:

TreeView_PopulateNode(ctl00_tvSysMgtNavigation_Data,0,ctl00_tvSysMgtNavigationn0,ctl00_tvSysMgtNavigationt0,ctl00_tvSysMgtNavigationt0i,' ','Management','Management','t','/*[position()=1]','t')

Is there any known confusion between the ClientCallBack done by the TreeView and ATLAS?

regards

Update:

The problem seems to exist only when ExpandDepth= "0", if I place a number greater then 0, like 1 or 2, etc ... it works fine without any problem.

So the TreeView_PopulateNode is missing an object when it strats expanding form the top root.

This problem is not encountered when the TreeView is outside the UpdatePanel.

Thanks,

Did you test with Mode=Always?

<

atlas:UpdatePanelID="UpdatePanel1"runat="server"Mode="Always">

Same problem, now I am getting an exception at the end of the method, last line:

function TreeView_PopulateNode(data, index, node, selectNode, selectImageNode, lineType, text, path, databound, datapath, parentIsLast) {
var context = new Object();
context.data = data;
context.node = node;
context.selectNode = selectNode;
context.selectImageNode = selectImageNode;
context.lineType = lineType;
context.index = index;
context.isChecked = "f";
var tr = WebForm_GetParentByTagName(node, "TR");
if (tr) {
var checkbox = tr.getElementsByTagName("INPUT");
if (checkbox && (checkbox.length > 0)) {
for (var i = 0; i < checkbox.length; i++) {
if (checkbox[i].type.toLowerCase() == "checkbox") {
if (checkbox[i].checked) {
context.isChecked = "t";
}
break;
}
}
}
}
var param = index + "|" + data.lastIndex + "|" + databound + context.isChecked + parentIsLast + "|" +
text.length + "|" + text + datapath.length + "|" + datapath + path;
TreeView_PopulateNodeDoCallBack(context, param);
}

The problem is with CallBack that TreeView does to populate ondemand. But the question, why only when the ExpandDepth is 0, I get such an exception!!!

Regards

Hi:

As you all know, TreeView has a property called ExpandNodesFromClient, that is when set TRUE together with PopulateOnDemand, then once a node is clicked, a client-callback is generated to expand the children of a specific node.

Believe or not, I got an idea while I was sleeping last night. The idea is that, since I have the TreeView in an UpdatePanel, so an asynchronous request will be sent, why do I have to enable PopulateNodesFromClient? There is no use in fact to do so, since in all cases, an asynchronous request will be generated.

So once I set the PopulateNodesFromClient to FALSE, it seems to work fine.

I guess there is no better solution for this case.

Hope you will benefit from this experience.

Regards

Hi Haidar,

Do u have solution for a setting the scrolling bar to its initial position. Actually the scroll bar reset to zero all the time.

Here is my code : --

<

bodyonload="document.getElementById('TreePanel').scrollTop = document.getElementById('divscroll').value">
<atlas:ScriptManagerrunat="server"ID="ScpMgr"EnablePartialRendering="true"/>

<formid="thisFrm"runat="server">

..........

<inputtype="hidden"id="divscroll"runat="server"/>

<atlas:UpdatePanelID="TreeUpdtPanel"runat="server"RenderMode="Inline"Mode="Conditional">

<ContentTemplate>

<divid="TreePanel"onscroll="document.getElementById('divscroll').value = this.scrollTop;"runat="server"onclick="document.getElementById('divscroll').value = this.scrollTop;"Class="PageTable PanelTree"onprerender="document.getElementById('TreePanel').scrollTop = document.getElementById('divscroll').value">

<asp:TreeViewID="TreeHCR"runat="server"DataSourceID="HCRXML"OnSelectedNodeChanged="TreeHCR_SelectedNodeChanged"ShowLines="True"ExpandDepth="1"ShowExpandCollapse="true">

<DataBindings>

.....

</DataBindings>
......

</asp:TreeView>

</div>

</ContentTemplate>

<Triggers>

<atlas:ControlEventTriggerControlID="RepeaterSearchResults"EventName="ItemCommand"/>

</Triggers>

</atlas:UpdatePanel>

.............

</form>
</body>
</html>

I m trying to implement to set the pos to the values saved in the hidden box ...but its not working in Atlas.
Any idea how to put the values when the tree refreshed ...

Hello:

I guess couldn't understand you well, can you illustrate more on the problem please?

Thanks,

Hi,

just to avoid a thread duplication, I've answered the same questionhere.

Hello,

Just thought I should share this..

I also had a problem with TreeView control and it took me a while to find this thread..

I have a TreeView with several TreeNodes and each one has several ChildNodes with PopulateNodesFromClient set to True.

The error I was getting is the same "Objected Expected" JavaScript error and I ran out of luck until I found this thread and tried setting ExpandDepth to 0 or 1... Now the TreeView works just fine. FYI, without setting ExpandDepth, the property is set to -1.

Thanks.
-Moe