Hierarchic grid: use parent key field as parameter of child objectdata source

[Damien]

Hello,
I have a hierarchic grid. Something like that (I tried to keep only the interesting lines).
                        

<telerik:RadGrid ID="RadGrid1" runat="server">

 

               <MasterTableView AutoGenerateColumns="False"
                                     Name="LEVEL1"
                                     DataKeyNames="SourceID"
                                     CommandItemDisplay="Top"
                                     EditMode="EditForms"
                                     DataSourceID="ObjectDataSource1" >

 

                   <Columns>

                       <telerik:GridBoundColumn UniqueName="SourceID"
                                                       DataField="SourceID"
             ReadOnly="true" />

                   </Columns>

                    

                   <DetailTables>

                       <telerik:GridTableView AutoGenerateColumns="False"
                                                      Name="LEVEL2"
                                                      DataKeyNames="SourceID" 
                                                                                                            runat="server"
                                                      CommandItemDisplay="Top"
                                                      DataSourceID="ObjectDataSource4" >

 

                           <ParentTableRelation>

                               <telerik:GridRelationFields DetailKeyField="SourceID"
                                                                     MasterKeyField="SourceID" />

                           </ParentTableRelation>

 

                           <Columns>

                                   <telerik:GridBoundColumn UniqueName="SourceID"
                                                                       DataField="SourceID"
                                                                       ReadOnly="true" />

                                   <telerik:GridDropDownColumn UniqueName="ElementShortNameID"
                                                                          DataField="ElementID"
                                                                          HeaderText="Element Short Name ID"
                                                                          ReadOnly="false"
                                                                          DropDownControlType="RadComboBox"
                                                                          DataSourceID="ObjectDataSource5"
                                                                          ListTextField="ElementShortNameID"
                                                                          ListValueField="ElementID" />

                           </Columns>

 

                       </telerik:GridTableView>

                   </DetailTables>

 

                   </MasterTableView>

           </telerik:RadGrid>


At first level (MasterTableView), the records have a "data key name" (sourceID)
At second level, the records have also the same data key name (So I have a "grid relation fileds" between the two identifers)
At second level, there is another field (element) with a value provided by a radcombobox.
I want that, in edit mode, the available element values in the radcombobox depend on the sourceID.
See the following object data source:

<asp:ObjectDataSource ID="ObjectDataSource5" runat="server" TypeName="DataAccessLayer.DataSource.ElementDataSource" SelectMethod="GetElementsListBySource" >
                <SelectParameters>
                    <asp:Parameter Name="SourceID" Type="String"></asp:Parameter>
                </SelectParameters>
            </asp:ObjectDataSource>

It works correctly when I am in Edit mode in order to UPDATE a record. The sourceID used seems to be the one of the record.

But, when I enter in edit mode in order to INSERT a new record (via the "Add a record button"), the sourceID parameter, received by the objectdatasource method (GetElementsListBySource) is null. As the record still not exists, no sourceID can't be used.

My question is: How could a get the parent record sourceID to pass it to the objectdatasource method providing my elements ?
I would like, if possible, make that declaratively in the aspx file to keep the same usage of objectdatasource.

Thanks by advance.
Damien

[Tsvetoslav]

Hi Damien,

You can achieve your requirement by first attaching event handlers to the grid's ItemCommand event and the ObjectDataSource control's OnSelecting event. In the Item command event listen for the InitInsertCommand of a detail table and when caught raise a page-global flag. Then in the OnSelecting event of the data source check the flag and if true, set explicitly whatever value you need for the select parameter:

protected void ObjectDataSource5_Selecting(object sender, ObjectDataSourceSelectingEventArgs e)
{
    if (initInsertRaisedForDetailTable)
    {
         e.InputParameters["SourceID"] = ....//your value goes here
    }
}

Hope it helps.

Regards, Tsvetoslav
the Telerik team

[Damien]

Hi Tsvetoslav,
Your solution works perfectly for me. Thank you very much.
Regards,
Damien