[Solved] NodeExpand event fires twice

[niv kfir]

Hi,
I'm populating a treeView with: 
 TreeNodeExpandMode.ServerSideCallBack
and:

 <telerik:RadTreeView ID="tvScannedURLs" runat="server" 

            OnNodeExpand="tvScannedURLs_NodeExpand">

</telerik:RadTreeView>

My problem is that the tvScannedURLs.NodeExpand event is fires twice for every expand of a node on the tree.
It has no connection to the PostBack property of the page.

Any idea why?
Thanks,
Niv.

[niv kfir]

I solved this by adding a flag - Set on the first time the event fires,
and reset on page PostBack.

Not very elegant, but works.
Thanks,
Niv.

[Ryan Ewing]

I have this same problem, I don't really understand what you did, but wrapped the entire function with an "If not e.node.hasControls then", If the node calling this has controls, I know the event has already been fired once.

Is there any progress on why this is happening?

[Yana]

Hello,

Could you please paste some sample code which will help us reproduce the issue?

Greetings,
Yana
the Telerik team

[Ryan Ewing]

He is a simple example where this happens:

aspx

 

 

<%@ Page Title="" Language="VB" MasterPageFile="~/Research.master" AutoEventWireup="false" CodeFile="treetest.aspx.vb" Inherits="treetest" %>

<asp:Content ID="Content1" ContentPlaceHolderID="cHead" Runat="Server">

</asp:Content>

<asp:Content ID="Content2" ContentPlaceHolderID="cc" Runat="Server">

<telerik:RadScriptManager ID="RadScriptManager1" runat="server">

</telerik:RadScriptManager>

<telerik:RadTreeView ID="RadTreeView1" runat="server" Height="300px" Width="400px" OnNodeExpand="RadTreeView1_NodeExpand">

</telerik:RadTreeView>

</asp:Content>

 

aspx.vb

Partial Class treetest

Inherits System.Web.UI.Page

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

If Not IsPostBack Then

For i As Integer = 0 To 10

Dim sectionNode As Telerik.Web.UI.RadTreeNode = New Telerik.Web.UI.RadTreeNode

sectionNode.Text = i.ToString

sectionNode.Value = i.ToString

sectionNode.ExpandMode = Telerik.Web.UI.TreeNodeExpandMode.ServerSideCallBack

sectionNode.PostBack = False

RadTreeView1.Nodes.Add(sectionNode)

Next

End If

End Sub

Protected Sub RadTreeView1_NodeExpand(ByVal sender As Object, ByVal e As Telerik.Web.UI.RadTreeNodeEventArgs) Handles RadTreeView1.NodeExpand

Dim sectionNode As Telerik.Web.UI.RadTreeNode = e.Node

For i As Integer = 0 To 10

Dim pageNode As Telerik.Web.UI.RadTreeNode = New Telerik.Web.UI.RadTreeNode

pageNode.Text = sectionNode.Value & i.ToString

pageNode.Value = sectionNode.Value & i.ToString

sectionNode.Nodes.Add(pageNode)

Next

'sectionNode.Expanded = True

End Sub

End Class

if you put a breakpoint on radtreeview1_nodeExpand you will see that is fires twice for each click, also it put the subnodes in twice.

 

 

[Yana]

Hello Ryan,

You should subscribe to the event either in the markup or in the code-behind with  "Handles", so please remove one of the these and the event will be fired only once as expected.

Kind regards,
Yana
the Telerik team