I'm having a problem in radtreelist and it isn't loading on page load
the radtreelist is inside a radmultipage the code is like this :
server side :
<telerik:RadTabStrip ID="RadTabStrip1" runat="server" MultiPageID="RadMultiPage1" SelectedIndex="0" ReorderTabsOnSelect="true" Align="Justify" Width="220px" > <Tabs> <telerik:RadTab Text="<%$Resources:Strings,Stores %>" > </telerik:RadTab> <telerik:RadMultiPage ID="RadMultiPage1" runat="server" Width="100%"> <telerik:RadPageView ID="StoresPageView" runat="server"> <telerik:RadAjaxPanel ID="Ajpanel" runat="server"> <telerik:RadTreeList ID="StoreTreeList" runat="server" HideExpandCollapseButtonIfNoChildren="true" ParentDataKeyNames="PARENT_STORE_ID" DataKeyNames="STORE_ID" AllowPaging="false" GridLines="Horizontal" AutoGenerateColumns="false" AllowSorting="true" AllowMultiItemSelection="true" OnNeedDataSource="StoreTreeList_NeedDataSource"> <ItemStyle HorizontalAlign="Left" /> <ClientSettings><Scrolling UseStaticHeaders="true" AllowScroll="true" /> </ClientSettings> <Columns> <telerik:TreeListSelectColumn ></telerik:TreeListSelectColumn> <telerik:TreeListTemplateColumn Display="false" > <ItemTemplate> <asp:HiddenField ID="hf_StoreID" runat="server" Value='<%# Eval("STORE_ID") %>' /> </ItemTemplate> </telerik:TreeListTemplateColumn> <telerik:TreeListBoundColumn DataField="STORE_NAME" HeaderText="Stores" > </telerik:TreeListBoundColumn> </Columns> </telerik:RadTreeList> </telerik:RadAjaxPanel> </telerik:RadPageView>protected void StoreTreeList_NeedDataSource(object sender,TreeListNeedDataSourceEventArgs e){ BindTreeList();} private void BindTreeList() { StoresDT.Select("STORE_ID=" + new WebSiteDataHelper().SelectedStoreID.Value)[0]["PARENT_STORE_ID"] = 0; StoreTreeList.DataSource = StoresDT; } protected void Page_Load(object sender, EventArgs e) { if (!IsPostBack) { StoreTreeList.ExpandAllItems(); } }