Grouping in RadListView Keeps Giving

[Mansoor]

Hi,

I have a site where I display a list of available Camps that the users can register for.  What I would like to do is group them by "CampStartDate".  I have the code below but no matter how I try to group, I always get the error "The RadListView control does not have an item placeholder specified."

 

<telerik:RadListView ID="RadListView1" ItemPlaceholderID="DataGroupPlaceHolder2" DataGroups="CampStartDate" GroupPlaceholderID="DataGroupPlaceHolder1" runat="server" DataKeyNames="CampId" Skin="Bootstrap" OnSelectedIndexChanged="RadListView1_SelectedIndexChanged">
                <LayoutTemplate>
                    <asp:Panel ID="CampHolder" runat="server">
                    </asp:Panel>
                </LayoutTemplate>
                <GroupTemplate>
                     <div class="vc_row wpb_row vc_inner vc_row-fluid">
                        <asp:PlaceHolder ID="CampsHolder" runat="server"></asp:PlaceHolder>
                    </div>
                </GroupTemplate>
                <ItemTemplate>
                        <div class="rlvI vc_col-sm-4 wpb_column vc_column_container ">
                        <asp:Label ID="CampNameLabel" CssClass="camptitle" runat="server" Text='<%# "Camp: " + Eval("CampName") %>' />
                        <br /><br />
                        <strong>Start Date:</strong> <asp:Label ID="CampStartDateLabel" runat="server" Text='<%# Eval("CampStartDate", "{0:D}") %>' />
                    </div>
                </ItemTemplate>
                <AlternatingItemTemplate>
                    <div class="rlvA vc_col-sm-4 wpb_column vc_column_container ">
                        <asp:Label ID="CampNameLabel" CssClass="camptitle" runat="server" Text='<%# "Camp: " + Eval("CampName") %>' />
                        <br /><br />
                        <strong>Start Date:</strong> <asp:Label ID="CampStartDateLabel" runat="server" Text='<%# Eval("CampStartDate", "{0:D}") %>' />
                    </div>
                </AlternatingItemTemplate>
                <EmptyDataTemplate>
                    <div class="RadListView RadListView_Bootstrap">
                        <div class="rlvEmpty">
                            There are no camps to be displayed.</div>

                    </div>
                </EmptyDataTemplate>
                <ValidationSettings EnableModelValidation="False" EnableValidation="False" />
                   <DataGroups>
                     <telerik:ListViewDataGroup GroupField="CampStartDate" DataGroupPlaceholderID="DataGroupPlaceHolder1"
                         SortOrder="Ascending">
                         <DataGroupTemplate>
                             <asp:Panel runat="server" ID="Panel4" GroupingText='<%# (Container as RadListViewDataGroupItem).DataGroupKey %>'>
                                 <asp:PlaceHolder runat="server" ID="DataGroupPlaceHolder2"></asp:PlaceHolder>
                             </asp:Panel>
                         </DataGroupTemplate>
                     </telerik:ListViewDataGroup>
                 </DataGroups>
            </telerik:RadListView>

[Konstantin Dikov]

Hi Mansoor,

The error is thrown due to the missing placeholder in the LayoutTemplate and the GroupTemplate:

<LayoutTemplate>
                   <asp:Panel ID="DataGroupPlaceHolder1" runat="server"></asp:Panel>

<telerik:RadListView ID="RadListView1" ItemPlaceholderID="DataGroupPlaceHolder2" DataGroups="CampStartDate"
    GroupPlaceholderID="DataGroupPlaceHolder1" runat="server" DataKeyNames="CampId" Skin="Bootstrap" OnNeedDataSource="RadListView1_NeedDataSource">
    <LayoutTemplate>
        <asp:Panel ID="DataGroupPlaceHolder1" runat="server"></asp:Panel>
        <asp:Panel ID="CampsHolder" runat="server">
        </asp:Panel>
   </LayoutTemplate>
    <ItemTemplate>
            <div class="rlvI vc_col-sm-4 wpb_column vc_column_container ">
            <asp:Label ID="CampNameLabel" CssClass="camptitle" runat="server" Text='<%# "Camp: " + Eval("CampName") %>' />
            <br /><br />
            <strong>Start Date:</strong> <asp:Label ID="CampStartDateLabel" runat="server" Text='<%# Eval("CampStartDate", "{0:D}") %>' />
        </div>
    </ItemTemplate>
    <AlternatingItemTemplate>
        <div class="rlvA vc_col-sm-4 wpb_column vc_column_container ">
            <asp:Label ID="CampNameLabel" CssClass="camptitle" runat="server" Text='<%# "Camp: " + Eval("CampName") %>' />
            <br /><br />
            <strong>Start Date:</strong> <asp:Label ID="CampStartDateLabel" runat="server" Text='<%# Eval("CampStartDate", "{0:D}") %>' />
        </div>
    </AlternatingItemTemplate>
    <EmptyDataTemplate>
        <div class="RadListView RadListView_Bootstrap">
            <div class="rlvEmpty">
                There are no camps to be displayed.</div>
        </div>
    </EmptyDataTemplate>
    <ValidationSettings EnableModelValidation="False" EnableValidation="False" />
       <DataGroups>
         <telerik:ListViewDataGroup GroupField="CampStartDate" DataGroupPlaceholderID="DataGroupPlaceHolder1"
             SortOrder="Ascending">
             <DataGroupTemplate>
                 <asp:Panel runat="server" ID="Panel4" GroupingText='<%# (Container as RadListViewDataGroupItem).DataGroupKey %>'>
                     <asp:PlaceHolder runat="server" ID="DataGroupPlaceHolder2"></asp:PlaceHolder>
                 </asp:Panel>
             </DataGroupTemplate>
         </telerik:ListViewDataGroup>
     </DataGroups>
</telerik:RadListView>

You can also refer to the following online demos for the grouping:

• http://demos.telerik.com/aspnet-ajax/listview/examples/grouping/defaultcs.aspx 
• http://demos.telerik.com/aspnet-ajax/listview/examples/datagrouping/defaultcs.aspx

Hope this helps.


Regards,
Konstantin Dikov
Telerik by Progress