stop postback on Collapse Client event

[Francesco]

Hi, I wolud like to stop postback call on collapse event. How I do?  I have a Panel bar that on click (server) bind a grid inside him and expan panel. This is ok, but them when I click on expand panel the control recall server side, and then, collapse panel. I wolud like to call serve when expand but not then collapse. Can I do?
thank

<telerik:RadAjaxPanel ID="RadAjaxPanel1Contratti" runat="server" Height="100%"
                    LoadingPanelID="RadAjaxLoadingPanel1"
                    ClientEvents-OnResponseEnd="adjustSizeEnd"
                    ClientEvents-OnRequestStart="adjustSizeStart">
                    <telerik:RadPanelBar runat="server" ID="RadPanelBarContratti"
                    AllowCollapseAllItems="True" Width="100%"
                    CssClass="panelBoxOut"
                    onitemclick="RadPanelBarContratti_ItemClick"
                    OnClientItemExpand="OnExpand"
                    OnClientItemCollapse="OnCollapse">
                        <Items>
                            <telerik:RadPanelItem Text="Contratti" value="pnlDataAnagafica">
                                <Items>
                                    <telerik:RadPanelItem Value="Grid">
                                        <ItemTemplate>
                                        <div class="panelBoxIn">
                                            <telerik:RadGrid ID="grdContratti" runat="server" DataSourceID="ObjectDataSourceContratti"
                                            GridLines="None" Visible ="False" AutoGenerateColumns="False">
                                                <MasterTableView>
                                                </MasterTableView>
                                            </telerik:RadGrid>
                                        </div>
                                        </ItemTemplate>
                                    </telerik:RadPanelItem>
                                </Items>
                            </telerik:RadPanelItem>
                        </Items>
                    </telerik:RadPanelBar>
                </telerik:RadAjaxPanel>

[Shinu]

Hello Francesco,
You can achieve the same by subscribing to the RadPanelBar client side event OnClientItemClicking and cancel the postback from there. Here is a sample code.
Javascript:

function OnClientItemClicking(sender, eventArgs)
  {
       var item = eventArgs.get_item();
       if (item.get_expanded())
       {
           item.collapse();
           eventArgs.set_cancel(true); // Cancel the postback
       }
  }

Thanks,
Shinu.

[Francesco]

WOW, work great!!!!!  Thank a lots